Mob pathfinding is sketchy

What I expected to happen was...:
I thought the mooshroom would jump up on the block that was 1 level higher to follow me because I was holding Wheat and it was "interested" in me as it would follow me with its gaze

What actually happened was...:
The cow was still "interested" but just walked back and forth and sometimes pivoting in place and did not jump to clear the block in front of it.

Steps to Reproduce:
1. spawn a mooshroom, or any mob
2. harvest, or cheat some wheat into your inventory X
3. try to get the mooshroom to follow you up a set of blocks in the "stair" shape, but not the stair block eg. XX