make sure your shoulders are in the correct place?
Interesting comment. I find that the more I "worry" about getting through a passage, the higher my shoulders go. Of course, the higher they go, the tenser I am, and the less likely I am to succeed getting through the passage. A CONSCIOUS effort to relax them, and as a result, my back, legs and calves, makes all the difference.
I doubt that 0.3 of an inch in bench height would make that much of a difference. You can change that elevation just with how you sit.
George