[pezuqxxe] Chess engines at different time controls

Chess engine X beats Y at one time control, but loses at a different time control, averaged over many games of course.  Investigate what is going on.

The problem manifested in TCEC, wherein developers struggled to test whether a given change improved the engine's performance at long time controls.

Assuming source code to both engines, how can one create a hybrid that is as good as both?

One possibility for the difference between time controls is parallelization efficiency.  Control for this by using only 1 core.