This just shows how much the Doctor cares about Clara. He wanted to make sure th…

This just shows how much the Doctor cares about Clara. He wanted to make sure the man she chose to love was good for her because he knew how much she loved the old him even after everything he did to her on Trenzilore and she didn't want him to change and he left. He knows how much that hurt her so he wanted to make sure her boyfriend wouldn't do the same as he did and leave such an amazing woman like her