If you get a bad roll, you get a bad roll. That happens regardless if you soak or dodge.
But, I will admit, my example assumed that soaking would succeed on every die. That's not likely to happen, really-- on six dice vs TN 2, you're likely to get five successes, yes? Three negate the attack in my example, the last two stage it to serious. If your numbers are correct, on an average dodge roll with these givens, you're also looking at a serious.
So, the odds say if you don't completely dodge, you'll end up in about the same place. But if you do completely dodge, you take nothing. So, there's no real risk in going for the dodge.
But, I will admit, my example assumed that soaking would succeed on every die. That's not likely to happen, really-- on six dice vs TN 2, you're likely to get five successes, yes? Three negate the attack in my example, the last two stage it to serious. If your numbers are correct, on an average dodge roll with these givens, you're also looking at a serious.
So, the odds say if you don't completely dodge, you'll end up in about the same place. But if you do completely dodge, you take nothing. So, there's no real risk in going for the dodge.
there are some important differences regarding bad rolls, though.
1) bad rolls happen a lot less often against TN 2 than against TN 4.
2) related to the above, a roll that would be bad against TN 4 can be excellent against TN 2.
3) in your example, you don't need "not a bad roll" for it to be a good idea. you need it to be a *perfect* roll.
if i roll 1, 3, 2, 3, 2, 5, 3... that's a lousy roll against TN 4, but not a bad roll at all against TN 2.
and no, the odds don't say you'll end up in the same place if you don't completely dodge in your example, unless i'm remembering wrong; as i recall, you need two successes to stage the damage in either direction. a dodge with 2 hits means you need 3 successes on your 2 body dice to reduce the damage by one level (there's one level left over to reduce, then two more to reduce damage to serious). even if one success is enough, the soak is *vastly* more likely to avoid deadly damage, and is much more likely to stage down to moderate than the dodge is to reduce damage down to serious.
the only way you can reasonably expect better results from dodging consistently is if your dice are loaded.
there are times where it is better to dodge, and there are times when it is better to soak. anyone following the mantra that they should always dodge is going to be taking a lot more damage than they need to, unless they are cheating.
soaking does not have to reduce damage to 0 to be worthwhile. it merely has to produce better results than dodging could.