This is probably something a trainer would be better at answering, but I'll give it a go ...with the kick off/wings level technique if you get the flare wrong and you float you can start being blown downwind, towards the runway edge. On the other hand with sideslip/wing low technique you can get the fuselage and gear aligned with the runway well before the threshold, so as long as you hold the sideslip during the flare you shouldn't start drifting sideways.
Personally having gone to the 777 having spent a long time on the jumbo, where you got a wing low at your peril (risk of outboard pod strike), I'm more comfortable with the old kick off technique but then transition to a bit of a sideslip in the flare.........it's a bit hybrid but I've noticed a lot of guys do similar.