I'm laying 2" x 2" tiles over a raised concrete patio slab that is 11' 6" by 16' 1 1/4". The tiles come in 12" x 24" sheets with the individual tiles joined by little blobs of a rubbery substance. Across the width of slab I think it will work out nicely. But going the other way I've got to either make the slab 3/4" longer or gain 1 1/4" over the 16' 1 1/4" dimension. If I put the extra space between the sheets of tiles that works out to adding about 1/16" (1.2 mm) between each sheet. Since the tiles are spaced 1/8" (3 mm) apart in the sheets this seems like it would result in a noticeable difference.
So, I'm wondering how large a difference would be noticeable? For example if I cut the sheets apart in the middle, I could increase every third by a bit more than a 32nd of an inch. Would that stand out?