I've searched, but this doesn't seem to be ticketed. It's a bug that's as old as the existence of reflection and passthrough, and it's....problematic...to TSB and a few other cases.

Take a shield or armor that reflects a damage type. the ion reflector in stock is a good one. Take a weapon of that damage type that has passthrough (eg. katana). Fire it at the shield. When the weapon passes-through, it will do so as well as reflecting, resulting in the shot duplicating. This stacks, so it can result in 1: a lot of lag & 2: random things in the area getting blown apart by magic duplicating deathrays.

Also, the larger the thing getting hit, the more the shot can duplicate. So while a playership isn't *that* bad when it gets hit.....a capital ship? That gets very bad indeed.

In the case of reflection, passthrough should probably be disabled if the shot is reflected (rather than the opposite occuring.)

(the austroraptor in TSB was/is particularly prone to this. When it was initially released into the beta [a long time ago], I had a stupidly overpowered plasma weapon with 100% passthrough. Firing a single plasma bolt from that thing at the original-flavour Austroraptor resulted in this: https://dl.dropboxusercontent.com/u/4915761/Passthroughfunforeveryone.png )