According to the Vintage Trek web page, the 1984 Trek 720 did in fact have a *Trek* investment cast bottom bracket.
You can find both the frame description and parts list here:
http://www.vintage-trek.com/
As was mentioned, the only Cinelli parts were the Stem and Bars.
Sadly, this frame is too small for me, and I have been looking for a while for a Trek 720 frame. A long time ago, I worked at Velocipede Peddler, which was a Trek dealer. I got my Trek 710 there on the employee purchase plan, and I still have that bike today. Since then, I've also picked up a 1979 Trek 930 frame via a garage sale and I'm almost done rebuilding it. My friend who now owns VP had at the time a Trek 728 and I've been quite nostalgic about that and other old Treks ever since. (if you've got a line on an available 1983, 1984 Trek 720 in the 22 1/2" size, please let me know).
Like several others, I'm wondering what the motivation is to so prominently and repetitively mention Cinelli in this ad. Who would be aware enough to flash on the name Cinelli but uninformed enough to think that there was a Trek/Cinelli collaberation?
rob hawks
richmond, ca