I want a kicker that kicks at 100% but nobody does. Not Sinfield at his peak, not Harry Smith, not Andrew Johns.
We should choose our kicker based on the best technique. A better technique is less likely to falter in a pressure situation. It strikes me that Thewlis has a pretty decent technique. If we stick with him, and his attitude to practice is right through his career, his percentage will get better (as Sinfield's did)