My initial thought is it would not make a difference. I'm going to grab some random numbers, say 30 tooth gears and 120 link chain. If 2 gears are each 30 teeth it would seem they will run the same speed if the chain is 120 links long or 119.

But if the drive is turning 40 RPM that is 1200 links per minute. The driven is 30 teeth so it turns 40 RPM.  But if there are 119 links the driver has to turn and extra 1/3 RPM to provide the drive gear with 1200 links per minute. So to perfectly sybcronize the chains must all be the same length.

Makes me wish I had went on the study ag engineering. Or at least Algebra 2.