When adding rotating lights for observers, there is a noticeable decrease in frame rate. The light emitting from the  Redstone lamps is delayed but catches up only when the user is jumping.

Steps to Reproduce:

To begin, construct a 3 by 3 square in which each observer is facing toward the dot on the observer. Next, add more observers facing downwards on top of the original 3 by 3 square of observers. In the four corners where the face of the observers meets the back dot of the second observer, insert redstone dust. Finally, place redstone lamps on top of the observers to make the build four blocks tall.

Observed Results:

The Redstone lamps do not rotate their lights, but they can rotate by repeatedly jumping up and down.

Expected Results:

The Redstone lamps rotate their lights without jumping up and down