Here is one tiny spin off. Because of your observation re the difference between the Intervals 1 and 3, I started hoping both could be had and started mucking around with crew settings a bit. I noted in
http://www.subsim.com/radioroom/showthread.php?t=85656
that there was some confusion about FATIGUE_COEF
Here is what I found that differs...
RegularFactor#0 is an ANYTIME fatigue hit for moving crew into the compartment, not just when surfaced.
RegularFactor#1 is not known, but I have an idea on flushing it out.
I am going to play with the settings below for a while. Sooner or later the trigger will occur and I will have a fatigue bomb that will wipe out everyone but Damage Control and Aft Torps. Hopefully I will at least have a clue what caused it

If someone else wants to booby trap but exclude different compartments it may lead to a discovery sooner. It could be a damaged compartment modifer or something like that. Knowing it would likely be useful.
;RegularFactor#1 = unknown - waiting...
; ;Twr
RegularFactor11=0.4;R/S
RegularFactor21=0.4;Cmd
RegularFactor31=0.4;Die
RegularFactor41=0.4;Ele
RegularFactor51=0.4;FwT
; ;FwQ
; ;AfQ
RegularFactor81=0.00004;AfT
: ;DG
: ;AA
RegularFactor111=.00004;D/C ; very minor hit