Well, my 1987 Audi 5000 turbo quattro (which weighs about the same as my 850t) with boost mods can almost match that (it can be a sub 7 second car--if I do an abusive launch) at almost 200k miles old. It feels faster than my 1994 850t automatic, but not by much, and the difference is the stick vs. slushbox. If "geartronic" shifts quickly and has minimal power loss through the torque converter (does it have one or is it a real "paddle shifter" ala Ferrari and BMW???) the numbers are entirely possible. Look what a scubie-doo WRX can do.

So yeah, it can be for real. Nice wagon!