IMO, Clay pitched better than the boxscore shows. Yes, he allowed a lot of baserunners, but a few of those were the result of some bad "breaks". Two positives from his start are that he only walked one batter and he gave up 0 homeruns. I think Clay deserves credit for hanging tough, battling through it, and limiting the damage, something that he is often not able to do. On most days, a start like that is good enough to get your team the win.
I think it's possible that he was sincere in his apology to his team about not doing his job in that second start (specifically with not backing up bases), and that he really tried to stay focused this game when he got into tough spots.
As far as whether it will be a confidence builder for Clay or not, who knows? You would have thought his Opening Day start would be a big confidence builder for him, and he comes out in his second start and absolutely stinks. He remains an enigma.