I bought a bunch of packs of FFG card sleeves and noticed that the square corners of the sleeves 'spike' quite sharply into you hand as you hold and manipulate your cards, making for a slightly uncomfortable gaming experience.

Anyone else found this to be the case? And if so, what do you do about it?

Is this normal for card sleeves in general or is it only FFG ones that do this?

I usually refrain from holding them in such a way as to jam the corners of the deck into my hand, but thats just me.

Yes! I'm sure I'll have to learn to do the same.

Or somehow round all the corners off?

Normal wear and tear will fix that problem. The more you handle them the more rounded the corners will get. My Descent Overlord deck is sleeved (as well as all other cards) and it is much easier on the hands after a few games.