Hi Gambo,
Yeah I think I had come up with a similar way of finding the "gap" seasons when I realized Fisk was missing, but it had been awhile since then and I couldn't remember exactly what I did.
I think I was playing OOTP 9 when I first started my league in 1970, so that's why Fisk was missed. I'm glad OOTP 11 supposedly handles "gap" seasons, but with a lot of things (like importing real rookies) I like to go behind and check to make sure OOTP isn't missing anything.