My natural sitting position has one leg facing too far outwards. This makes it difficult to pedal with that foot.
Clipless allows me to force said leg into a normal riding position. However, that leg is still having issues adapting to the new position.

I find accelerating while pulling to be a drastic increase in efficiency. Plus, when the bottoms of my feet start hurting I tend to switch entirely to pulling for a while. How can you do that without being clipless?