How about, as you found repeating x-y was useful for locating the block of 7 layers in the first place; I'd be incredibly curious if, knowing that block of 7, if you then iterated from repeating x-y in that block z times.

Like for those 7 layers 1,2,3,4,5,6,7 does efficiency increase if you run 1,2,3,3,4,4,4,5,6,7 or perhaps 1,2,3,3,4,5,6,6,7 etc. If only GPUs grew on trees