To break away requires you to put out 30% more power than the person behind you, and then also means you need to put out 30% more power than the rest of the field. That is a good recipe to go out hard, overcook, and then get passed up by the entire peloton.

The 30% - Drafting is good for a 30% power increase. When in the middle if a peloton, even more. The breakaway plan can make sense, but not by fooling around in a TT helmet in the middle of a peloton for a few hours first.