Nope, didn't hit the limit. Generally I don't go through that many lives in an hour even in the MA where I often fly a lot more stupidly than I do in the CT. I feel 6 lives doesn't really have that much of an effect if you fly halfway smart. And if you do a couple of bomber sorties (and do them properly, not low-level "kick me" runs) then they can take over an hour in their own right.
Four, as Erg suggested, sounds like it might have more of an effect. A good sortie fighter sortie in the CT I've found genrally lasts about 15-20 minutes for me, regardless of the outcome.
I was a little confused as to definition of life, and maybe that could be clarified in the MOTD. Wasn't sure if it was actual deaths that were counted, or rides (i.e., are bails and ditches counted against the total).
It's a great idea tho, keep playing with it.