Hi. First off, please do not resurrect old threads to simply ask questions UNLESS I have contributed something new or updated them. This is technically necro-ing and could get my threads closed, which would annoy me to no end. If you have questions, use my private messaging function here to ask me questions. Or, start a new thread.
Secondly, I will answer your question. THIS TIME.
So would you say, then, that this might imply that torpedoes have a capability to bypass shielding?
Well, evidently they do. We just aren't sure what the mechanism for penetration is, and there's not any "single" consensus about how it does it.
As Grand Admiral Ancaris points out, slow moving attacks can bypass shields.
It could also get by the shields by being technobabble. Anything involving the tyranids is inherently technobabble. I dislike that statement because t have any real range (thousands/tens of thousands of km) it would have to be guided OR to travel at a high velocity that would strike in a few seconds at most, and the latter won't mesh with the "slow moving" bit.
Of course, alot of that is interpeting gameplay, so it may refer to some momentum-based "penetration" effect. Torpedoes are big, massive, and tough as nails. They're designed ot punch through hulls and they may be designed to brute force through shields as well (so much momentum they can knock out the generators or short them out.)
Or, it may be technobabble. I favor the latter, but as I said, my view is hardly the sole one.
But the text states that "the first missile hit the palace at tremendous speed", so it would seem that it didn't get past those shields due to moving slowly. It got past them some other way. So could we be looking at "shield breaker" torpedoes? Similar to the shield-breaker ammunition that Vindicare Assassins carry around for their Exitus Rifles?
Perhaps. I have noted that in Shadow Point fighteres were threatene dby destruction by the activation of void shields despite having little or no velocity, so there may be some shield penetration qality. Or there may not be, and its just a matter of momentum. Or, there may actually BE some speed based limitation on torpedoes. Or it may be a combination of effects.
And if so, how common would such torpedoes be? Do all torpedoes move at similar speeds, or are some much slower (and as such, capable of penetrating void shields without any "shield-breaking" effect)?
No way to tell. Given the way technolgoy in the Imperium works, it could even vary depending on the kind of shield or the kind of torpedo. Discussion of void shields occured in the 3rd/4th edition 40K analysis thread when I was covering the Orks, so you might want to check those out.