I found the exact post that describes the complete workflow in 3DS Max (including a fairly detailed video of someone using the same tool to mod RE 6). The reason I ignored it in the past is that the tutorial only used one bone as an example, but the video went more in-depth. So yeah, it's totally nowhere near as difficult as I expected, so long as you already have a decent knowledge of modeling, UVing, and rigging. If only DMC 3 were this easy to mod! Still, I haven't tried it yet so there may be some hiccups that aren't shared with Resident Evil.
http://s1.zetaboards.com/InfernalWorks/topic/5487960
What would be a good way to test it that you guys would actually like to have? Something I could mesh quickly and rig to multiple bones... nothing comes to mind just yet, unless I'm just replacing one article of clothing. I could make a full costume, but I'd definitely like to test out something a bit less time-consuming before putting in all that effort. *scratches head*
Anyway, this is totally off-topic, except to say that I'll want to make a corrupted Vergil costume if it doesn't come with the Special Edition. Also, DanteSparda08, I can totally see the images now if I copy their location, but I suppose the site they're hosted on doesn't allow hotlinking.