If his goal was to get right back on the field ASAP, then choosing to spend a few aimless months with MIN was not going to do that for him. That's the part I don't get on that end...He was releases in November. Bad teams aren't looking for a QB in November unless they literally have nobody to play the position and good teams are usually in good shape at the position and would be like the Vikings, just signing a guy for depth at the veteran minimum to be on the practice squad. Him ending up with the Vikings likely had more to do with him wanting to work with O'Connell for a few months than about money. He made $36m last year, unless there is literally no market for him, he's not taking less than $10m-$15m and will likely get more with his level of experience and some reasonable stats as an NFL starter.
...unless he was told there was a reasonable chance he's on the field for MIN next season. Then it makes more sense. Otherwise, if he's going to sign a cheap deal probably with a ****** team anyway, he could've headstarted that already instead of sitting around in MIN.