It is foolish to resist. Give yourself to the dark side
It is true, a simply 99th percentile wont tell you how smooth the game is, now will frame time variance.
Scenario 1) The first few seconds of a the test has some memory hitching as some resources are loaded with minimum the 10-15FPS, afterwards the minimums are 70FPS
Scenario 2) There is not hitching, but minimums are frequently below 55FPS even when the average is 80+
Scenario 3) The start is fine but some time later there is a serious hitch while the GPU has to swap out a load of memory, but this only occurs over 1 frame, overwise min FPS in 70FPS.
Scenario 1 might provide the lowest minimums at the 99th percentile but it will offer the best experience.
As for smoothness, FPS that range form 40-45FPS ar much smoother than FPS from 70-110FPS, but I know what I would rather play with.
I 100% agree that how well the game plays is far more important that a average, but minimums and direct frame variance is not a good measure either.