I was also referring to single spaced. I found my post on the Columbia thread where I referenced that 2-3 page guideline. It's from the Wharton website.
From Wharton website:
https://www.wharton.upenn.edu/mba/admiss ... paring.cfm"Useful recommendation letters are usually two to three pages long."
Even though I'm not applying to Wharton I used this as a guideline when I prepped my reccomenders. Both my CBS reccomenders said their recs were about 2-2.5 pages.
I think Tuck limits recs to 300 words per Q, 4 Qs, so that's 1200 words which would be about 2 pages single spaced. And that's their max.
So, putting all that together, I would say 2 pages single spaced is probably a pretty good target for your reccomenders. I think I'm going to ask my reccomenders to try to shorten subsequent recs to 2 pages.