as far as i know, these things are part of armor, so can't be modified by training or such.
isn't there the quick draw slot for most armors anyway? 1x2 knifes fit in there perfectly. (also pistols. and grenades. and medipacks)
for any blade bigger than 1x2 (e.g. a fully sized sword) i don't think quick draw or having it hang next to your legs is a good thing, considering gun based combat...
(though having a 1x3 QD slot would be perfectly for stun rods)
Theoretically nothing forbids a 2nd QD slot for the other hand too though.
Also a lot of blade weapons wouldn't fit in a scabbard thats not comically big.
(And you´d have to have a special weapon group. or do you wanna put golf clubs or boom boxes in there too? ^^)