Fiend, the answer to your wonder over DD's training / injury / recovery conundrum is that he isn't actually ever recovering properly.
I think in this particular instance you may be right but what Fnid refers to runs deeper than just a couple of finger and shoulder injuries: meniscus tear and a hamstring rupture being 2 pretty big injuries that a) I recovered quickly from and b) havent shown any sign of recurring. The reasons for these in the first place is a whole other can of worms
Also I've been completely injury free for over a year and a half now so "(n)ever actually recovering properly" is a bit harsh... On balance it's probably because I do "tend" to heal pretty quickly that I ignored this tweak and am now paying the price...
:D