Hey! I can't believe I didn't see all of these comments from so long ago! I agree, you should only use the injury roll table if it 1) makes sense, and 2) makes the game more fun! To me, it makes sense in a one-on-one showdown for sure, and only sometimes in other circumstances. Play the way that works best for you and your table!
Thanks for the reply :)
Personally I think it only makes sense for me when facing a significant opponent.
If the PCs are dealing with a bunch of hired hands I don't want them crippled early in the game regardless of how realistic that might be, but if they are facing off against the arch villain of the game then sure ramping up the threat level feels appropriate.