Apologize to students? That's what gets me. I use purple and green - I don't like the red (too much hurts my eyes) and I want them to get over the knee jerk reaction when they get a paper back, especially with composition, which is a process. I do focus on strengths as well as weaknesses because they need something to build on - but man, the problems are there - discover your patterns and fix them. I'll help in the process. I do not apologize to students for marking on their papers or for giving them constructive criticism, and I don't allow them to apologize for their mistakes. I just say - good, now let's fix it. If you were perfect you'd be elsewhere.

Ack.