I'm not going to defend. SJax's performance or behavior last year. You can't. But I will say that he couldn't have been any worse at the end of the bench than TMac was. If you are going to waste a roster spot, you might as well waste it on a guy who knows the team, has had success, and who could be that guy who gives you something when every other SG on the team is struggling.
Many may not remember this, but in 2003, the Spurs top 2 PGs (Parker and Claxton) were terrible in the clenching game of the finals. But up stepped Steve Kerr, from his damn NBA deathbed, to play PG at the end of that game. And play his ass off in a way I hadn't seen him play before. That's what kept going through when I saw our guards falling apart in the last two games with TMac sitting there. Maybe Jack had one more in him, craziness and all.