Why can creationists give straight answers?

Couldn't you get from a common ancestor to chimps & man
with 1667/2 (if 1667 is an ok number ... dunno where it
came from but hey ...)?If the 1667 were split in half (I know, I know it's odd),
but where in different locations in the two lines,
you'd end up with 1667 differences.So from a common (and different genetically) ancestor, you would
have to split the 1667 amongst the two lines.Or however many mutations were actually accumulated.

Oh ... so the idea is that there could only have been
1667 fbm's from present back to a common ancestor
with chimps (or forward from it rather).But, yes that would be each, allowing a difference of
1667*2 = 3334 possible differences between chimp and man.What is the genetic difference between chimps and man?
How is the 4my (or is it 5) calculated?