So, I am sure that by now anyone who isn't LNP bound has discovered that force transfer mechanics have made certain things more deadly. Large creatures with high strength or those wielding heavy weapons can now do quite a bit more damage, even to those walking around like little adamantine tanks. Danger rooms are dead, as are many of the dwarves you sent into them to train. Overall, the changes are a great bit of realism and make the game more interesting.
However, it seems like in the process a change was made to make armor -more- effective at initial deflection, particularly of sharp pointy attacks. This seems to have been done to balance out with the fact that force gets transferred through, but it ends up with an issue when crossbows enter the mix. Because at this point, crossbows are completely incapable of piercing armor.
I ran a test firing(not in arena, though I plan to do some more serious science soon), on an invasion force decked out in full iron plate, trapped in a hole with 30 marksdwarves with a functionally unlimited supply of iron bolts. I fired ~2000 iron bolts at the poor trapped fools. Of the 10 invaders, there were no deaths. They all had severe wounds, repeatedly passed out from exhaustion, had their armor shredded, but none died. And scrolling through the battle reports, I could not find a single shot not deflected by the armor, even as the armor fell apart.
Of note: I have not tested with steel bolts. This issue is also definitely not true of copper armor, which even bone bolts seem to slice through like butter. And while it may be that softening up the enemy as opposed to just annihilating them is to be preferred for the way marksdwarves function, they don't even do that terribly well unless you manage to fire a truly absurd number of bolts to do so.
It feels to me like the answer to this is probably to up the velocity of bolts, though I worry this might make them over powered against unarmored targets.