"Very well. He has a SIN, but it is very confusing - the attached data appears to be a mixture of fact and fiction. It seems that much of the biometric data is falsified. He is under intense law enforcement scrutiny from certain quarters, so maybe certain government agencies have more accurate information, but if so, they are not sharing. Most of his birth information, however, I have confirmed through various shadowy sources," the sprite said with a wink. Continuing, "He was born 10 October 2015 here in Seattle. His father, deceased, was Thomas Finnegan, son of Rory and Mary Finnegan. Mary survives and wields considerable influence still in the Finnegan crime family. The subject's mother is Sophia Ciarniello, living, the sister of Vince "Numbers" Ciarniello, head of the Ciarniello crime family.
"Although the subject is considered a nominal member of the Finnegan family, he maintains close ties with the Ciarniellos as well. These family ties make him nearly untouchable as far as Mafia politics go.
"In addition, he seems to have inherited the Ciarniellos' touch with figures - he is considered a genius at calculating gambling odds. Since the Ciarniello family has a near monopoly on this sort of talent, Capa Rowena O'Malley holds onto him fiercely, apparently considering him a balance in the power struggle between the three families. Besides which, his numbers activities are one of the Finnegan family's most profitable ventures.
"It seems, however, that Louie is dissatisfied with his already grand status among the families. He pins his self-respect on being a "real wiseguy," as opposed to a pencil-pusher for the families. As such, he runs his own large crew out of a pasta place called Rudolpho's. They have taken it upon themselves to expand the Finnegan family's territory, and although they have been marginally successful, they are costing the family in terms of enemies made. But because of his close ties to key members of two of the three families, and his money-making prowess, no one has dared do more than gently hint that he is only making trouble, and those hints have apparently fallen on deaf ears.
"The new DA, Myers Rothstein, seems to think the subject's combination of recklessness and personal violence make him a perfect target for prosecution, from which point Rothstein probably hopes to move on to other key family members - few that are speaking doubt the subject could be turned, which would be disastrous to the Seattle families.
"So when some children recently witnessed a murder in which the subject was involved, it is rumored that Capa O'Malley herself ordered that they and their families be killed in order to silence them, and since Rothstein has yet to build a base of loyal officers, it was easy for the mob to suborn the police and target the supposedly 'protected subjects.'"

A) IC becomes very difficult to use on any item that you intend to use for anything else. I'm also not intimately familiar with SR3 matrix rules, but I am pretty sure this would be contrary to how they worked in that system so "not canon" might be an appropriate reason. Instead of hacking into a system where a hacker has to worry about probe IC calling in attack IC (multiple of them), the node MIGHT be running a single IC agent that is of any concern to the hacker - he certainly won't be going toe to toe with more than one - because the node would crash itself if it ever tried.
B) The "weight" of agents increases, which is just as much an advantage for the hacker than a disadvantage, when he dumps them on some unsuspecting node he has gotten into and reduces its rating due to sudden program overload.
C) Sprites become much much cooler. Which is nothing against Cattie, or technomancer's in general, but if a hacker's commlink can't hold more than a single IC and stil lbe usable, but a technomancer can effortlessly call up to their charisma in sprites, and still function at full capacity - there is a clear winner in that contest.

A) If a fully-equipped agent counts as a single program running on a node, there is very little reason that a corp node (someone with some money, cause rating 4 agents are 10K a pop) couldn't run 4 or 5 IC on the node at a time. This is more abouts what I remember from SR fiction and older editions, but I remember they would make a system neigh unhackable, since every round the hacker would have to roll against 5 perception attempts, and odds are he would fail one eventually.
B) There is very little reason not to run IC on a node - if you have it. Most hackers have an agent, and if they're not doing anything more important with it, they might as well have it runnign as probe IC and keepig an eye on their system. Even non-hackers with a little dough can protect their systems pretty effectivly by having an expensive agent constantly percieving in the matrix.
C) The "flood of agents" tactic, where a hacker (who, presumably bought 5 seperate agent programs, or took a year or so off to crack his program several times so that he could run more than once instance of it), loads like 4-5 agents on his system, and has them all exploit a system, or use teamwork rules, or something equally crazy. In a matter of minutes, one of them is bound to get in, and a few more are bound to put the system on alert - but since "alert" is on a per-user basis, the accounts made by the ones who succeeded are fine. Or, alternativly, the hacker logs into a system and uploads all 4-5 agents reducing the rating of the node he is hacking appropriately. This isn't any worse that the version of this from the otehr ruling, except that it takes 5 complex actions to do instead of 1.

Ok, as a counter to A and B, you need to remember that most, if not all, company nodes are true servers, capable of handling hundreds to thousands, if not up to hundred of thousands, of users at once. The amount of users or programs the server can run all depends on how much hardware they throw into the rig.
That being said, it would not be much more of a burden, more like a spit in the ocean, to throw a few agents onto the server. The whole problem with the 'weight' of agents can be felt on smaller machines, like commlinks, drones and equipment, who's ability to handle such a load is no where near that of a stationary server rig. You have to remember that there is only so much hardware you can throw into something the size of a phone, no matter how high tech it is, and if you had something the size of a server rack, you could throw that much more hardware into it.

Base it off today's tech and you can see my point. Your home computer can handle only so many programs running at once.
Now most companies have a server room stacked full of racks of hardware that act as one full computer. By doing so, they can handle more programs running at once and users accessing it at the same time. Take Yahoo, Amazon and Google for example. There is no way they could handle so much traffic at once if they were just running something with the power of a desktop.

The whole reason you assign a rating of 1-6 for a company node though, is because that is the amount of processing power it can extend to each process or user on the node without crashing itself under its own weight.
Commlinks have the same ratings, though split up into 4 categories, to denote that they are made to run for only one user instead of thousands.

As for C, while yes the statement is very correct. Though the fact is, a TM would have to compile and then register each sprite after the first she brought into play, and registered sprites are more likely to be lower in rank than just a compiled sprite. Then you have to figure the time it takes to actually register the sprites. All in all, it's a logistical nightmare to use that many sprites at once.

As a tactic for what BlackHat is doing with the single agent on his commlink if agents had all their programs count. He could load a single R5 agent with R5 Analyze to look for anyone by himself on the node. If it spotted something, it would raise the alarm and auto load another agent with fighting programs, along with unloading itself to free up processing power. (You don't need to look anymore since you found something) The fighting agent would probably have just Armor and one of the attack programs on it to save processing power still.
This example is what company nodes are most likely to use just to save processing power also. No need to have tanks running around your virtual city when beat cops looking for intruders will do. Yay, metaphors.