Consistent E.T's

After all the variables you mention above, now I begin to think even if E.T.'s repeat themselves, it is probably a different mix of factors each time. With subsequent runs, the variables probably cancel each other out, (some improve time, others slow it down) while they remix in a way which just happens to reload into the same elapsed time. Third and fourth attempts must become statistically more and more difficult to repeat, if for no other reason than ambient temperature changes.