Isn't "duplicate redundancy" itself redundant?
One thing I've noticed is that some GMs seem to have that as a positive strategy. Remember when the Knicks signed every PF? And how Detroit last Summer signed a shit ton of centers? I'm guessing the thinking is, if you have a bunch of the same type of player then you will really be able to see the one that's the best and you can flip the rest, whereas if you just sign one, he might be a lemon.
Of course, if that's the strategy, you don't keep re-signing them to massive contracts.