1. It doesn't buffer inputs. If you are travelling Left and quickly tap Up then Left, it'll treat it as a no-op instead of moving you up a row.

2. You can suicide by quickly tapping Up + Right while travelling Left. It'll fail to buffer the input, so you immediately turn 180 degrees back on yourself and die. If you're travelling Left, then you can't press just Right, but an intermezzo tap of the Up key bypasses the input validation that prevents a 180.

Useless.