This thread(and recording) makes a pretty good argument for ORTF.
http://www.taperssection.com/yabbse/index.php?topic=21093.0
I like Vanilla .......but, ORTF is trying to capture an image and I don't see much of an image coming from a single stack (read MONO from one side of the stage) when compared to 2 stacks w/ some separation. You can run AB or XY when stack taping (of course one can record any way one chooses). The guy running ORTF in front of the stack is using, IMO, what is easiest to him (which is just as good when capturing a single stack).
jah
some poeple like to argue that you can still get the stereo image of the crowd
to that I say wtf
Cuz of the mini rig I run ORTF (pretty much the only option with the mics in the case.) Even running in front of a single stack, there is still some imaging there. (as there are reflections, acoustics of the venue, etc) Personally I like it tho, it gives you more of a "sitting in front of the stack" feel than other configs. I aim it by drawing that line between the mics and pointing that at the stack...