I would only worry about isolating the 'small' stack when deep in the money or a sat with a determined no of seats paid and bubble approaching.
otherwise I will aim to increase my stack ..
have done and will when I have a big stack shove into a pot where I know the 'small' stack has a wide range and a few limpers come along as I want to be HU ..
ie..I have 20,000 chips..blinds 100/200 ...small stack with 1200 chips shoves and stacks of 10,000, 14,000 etc call I will shove esp if near the bubble with 55+ AK-A10 KQ-K10 QJ-Q10 J10....the other stacks likely fold and I am playing HU for 3600 chips (almost 20% increase to stack) with 3/1 pot odds
doesnt make you popular though