He was better than mediocre. Playing 15 years with a USFL title, and starting for 2 NFL teams for multiple years is a career far better than anyone here and most QBs that enter the NFL. He was tough as nails and could take a hit/stay in the pocket better than any QB in Saints history.
Not his fault he wanted to get paid, that's on Finks and cost the Dome Patrol more chances with the likes of Fourcade, Steve Walsh (horrible trade), Steve Buck at QB.