My "if its not mentioned...." comment was directed at the notion that you can't adjust to it. He basically said its not possible, there's nothing in the rules about it, so its GM call. Hope this clarifies.
You people are missing the point about my "its the only piece of cyberware to like, not replace anything" I was trying to convey the point that you aren't adding anything foreign. I'm starting to get kind of tired with this debate as nothing new is really being said anymore so I'm not caring as much how I word things. Sorry.

Bone lacing adds. muscle replacement adds. You can't control it naturally, only influence. Bone lacing doesn't need control as you add to the bones, so it the bone hits something or moves, the BL goes along for the ride.
MR is harder to buy but its still not a really big deal. A muscle either pushes or pulls, not both. Its not overly hard to imagine it being worked into the central nervous system so that it works in perfect coordination WHICH WOULD HAVE TO BE DONE. I doubt that's really possible but its not really worth debating as it doesn't matter. MR isn't going to make you fly off the handle and shoot someone in the face.
Wired Reflexes is hooked up to everything in the body but its certainly not fluid. Like I said, it activates in spurts, firing off electric signals to the rest of the body. It'll be passively active until an offending stimuli's prescene is detected at which point it fires off.
BR on the other hand is ALWAYS ACTIVE. Its ALWAYS FIRING SIGNALS. They aren't electric. They're the natural signals produced by the various glands (I forget the scientific name. Shame on me) and distributed across the body.
Initially its going to cause all sorts of hell. After a day or two of this it'll noticeably be improved. You're still frazzled, but you're learning to cope. It'll improve little by little over the course of let's say, a month. I don't know how long it takes to adapt to a dramatic change but its not going to take much longer than that I imagine.
It doesn't matter though because runners are like I said, kind of presumed to be at home with their implants. BR is going to be controlled a lot easier than WR.
You know why? The body doesn't NEED all of its nerve endings all the time. Its not going to use what it doesn't need. Now with BR I'm sure there's something in there that will rotate their use because they'll eventually wither and die without use.
This is what addiction does. You take a drug and it clogs the ends of your nerves just before the synapse so the neurochemicals (whatever they're really called..ugh I feel like an idiot) can't get through. Your body's solution? Grow more.
It'll keep doing this so long as that entrance to the synapse is blocked. Stop taking the drug? It gets cleared. Neurochemicals can flow through the once again. What happens to the unused ones? They complain bitterly. They whine and complain because they're hungry for stimuli and not getting any.
I think this is what's attributed to the shakes and discomfort associated with withdrawal. Your body is going through hell because its adapting to the sudden change of not having the drugs its become accustomed to using.
Anyways with BR that's what's going to happen. These nerve endings will be there and we'll presume kept functional (after all 2.8e is a helluva lot to pay so it makes sense). Normal life? Not going to be a big hassle.
Life threatened? All of those extra neural pathways will be pumping neurochemicals (can someone PLEASE tell me their real name?) quickly and efficiently. This will give you more chemicals to work with, increasing their effect, and thus, giving you boosted reflexes.
The same thing is accomplished with WR only its artifical electrical stimulation, not something you're going to really get used to.
I'm rather annoyed with the people who wrote these books. I doubt they picked up a science book or attended any basic anatomy and physiology class. I've taken an entry level one and I know enough to be able to debate it.
I took the class a couple months ago and I've forgotten a lot of it unfortunately. I've actually got a CD encyclopedia containing 4 CDs of information on the human body. I bet the designers of this game could've made jolly good use of it.
I'm not saying I know everything but gods, this is basic stuff and it should have been accounted for.

If I were designing a game that I cared about (which for me, would be a prerequisite, no questions asked) I'dve researched it. Asked a few people, seen some movies, whatever.
For a high-tech world you need to have a solid background on the basics. How hard is that? How LONG would that take? Not very. Hell, a few months in basic A+P, electronics, physics, etc types of courses and you've probably got enough factual information to work with.
Shadowrun's got an interesting history and a cool atmosphere but damn...a lot of what's in these books is bleh. Before you go and say "If you don't like it, don't play" slap yourself because if I didn't care, I wouldn't debate it, as I'm sure a lot of you do.
I care about this game. I want to succeed at it and I want to understand it. When fallacies, blank spots, hazy areas, and loopholes abound it leads to a lot of discussion.
Whether this all matters or not I don't know. I love debating, especially when its kept civil. I've enjoyed myself, its getting kind of stale, but that's to be expected.