Regarding the picture of Donovan: this step was a mistake….Dan has talked about how Donovan over-pushed @ about 70m (among many other imperfections Dan and Donovan have identified in that race), similar to how Bruny over-pushed one step in the Seville final. Also, if you watch the entire clip (or any film of Donovan) you will see that he always has more extension on his right side…..this was due to some fairly significant abnormalities in his hips (can't remember exactly what)……his left side is actually much better, reacting far quicker off the ground – this imbalance led to his trademark 'galloping' gait……
Mike….I would argue that 'triple extension' is only a useful coaching cue in acceleration develoment – ie. the first 6-7 steps – and maybe not even then (athletes cueing full extension @ the ankle joint can have a tendency to over-push and have problems with their angles; although cueing ankle extension in those who short step their acceleration can be useful…..).
I like your comparison to OL……generally, the OL who over-cues hip extension will never get under the bar at high loads.
Carl……name one sub-10 sprinter who reaches triple extension at max velocity (including BJ)….from Jesse Owens to Tommie Smith to Carl Lewis to Linford to Donovan to Maurice – all have been masters at limiting thigh angle behind the hip.
To be honest, I have no idea where all this 'triple extension' business got started, and just don't understand what the fuss is about.
To me, cueing it would lead to more problems than it would solve.