Suffering

I just returned from my level 2 yoga teacher training. Tonight was an intermediate yoga class on hip openers which I was apprehensive about. My hips are considerably less flexible than most other yoga teachers. I don't qualify as a pretzel even the soft squishy ones. The class went well and I was able to do some poses that I didn't think I could do. My attitude was more relaxed than usual and I think that made my body follow suit.
I watched part of Oprah and Eckhart's latest web class today. Eckhart told the story about a zen master watching a group of monks do archery. The master commented that one of the monks was draining his own energy by wanting to win too much. Oprah talked about when she ran track and would look back to see what the next guy was doing and lose her focus.
In yoga class I sometimes glance over at others and compare myself. I often feel better than or worse than them by doing it. I also lose my centeredness and inward focus. Than I can judge myself for being so competitive and un yogi like.
Today I still looked at others and I gently brought myself back from my comparing as soon as I noticed. That felt so much better to me. I don't have to be perfect, serenely focused on my deep slow breath the entire time. That expectation creates so much suffering. In fact so much suffering comes from expecting myself to be or do something I am not being or doing. I would like to carry this over to my yoga teaching so I could relax more and know I am doing a good enough job, more of the time. This is one of my goals for this level 2 training and for my life in general. How does wanting to do it perfectly or having unreasonable expectations of yourself create suffering in your life? How could you be more gentle with yourself?