I can't say I've ever had a problem with the abs coming on when I didnt want it. The only time its ever happened is when some tw@t pulled out in front of me on a slippy road and I had to do an emergency stop ( and I mean real emergency stop, not just a hard brake ). Thats the only time I've ever noticed it, and luckily it worked or I would have got stacked.
I know some of the 'experienced' drivers might start banging on about driver skill, cadence braking etc etc but when the poo hits the fan, everyone sticks their foot to the floor. If it wasn't for ABS....
Personally, if you honestly think it will make you brake better or you've been having problems with it, then disconnect it. But if its a case of 'my mate down the pub said....' then I think I'd leave it on, just in case