the mono x2 would be something that could be used in lieu of the 2GB autosplit fix to 2X longer runtimes than would be possible with poly/stereo wav file...it would require later mixing to get the merged stereo wav, but you cut in half the number of times you need to force a stop/start when recording
while dual-mono would be nice, I'd say in addition to the 2GB autosplit feature, definitely not "in lieu" of.
at 24/96, 2 gigs is about an hour. if you record it dual-mono (with two different files), you can get 2 hours at 24/96. I know I routinely tape sets that are 2 and a half hours in length, and need something to be able to continuously record for that time.
So it'd be a nice feature, but we still need a 2GB autosave and seamlessly start a new file.