About the only place I do lane split is along the left side of a right-turn-only lane when I'm going straight. You can normally safely go straight from there, and you don't block right turning cars.

No right turn lane? Or the right turn lane isn't safe? I won't filter up, but I will get right in the middle of the rightmost lane of straight traffic. Seems to be the safest place to be - every driver who sees you knows where you're going.

Going straight from the middle of the right turn lane isn't going to immediately cause problems, but might cause you some heartburn or worse at the far side of the intersection if you're forced to merge into accelerating traffic - oftentimes with drivers who want to beat you across the intersection.