There's no heresy at all in a faster stroke rate. It's a skill
- at least when you combine it with a strong effort to keep your stroke efficient, quiet and relaxed. What makes an effort to increase stroke rate a desirable part of practice is to increase it mindfully, not the heedless churning that's more common. Doing so with the Tempo Trainer is the best way to get both benefit and enjoyment - perhaps even a Flow experience - from doing so.
In every Tempo Trainer practice I do, usually 60% or more is devoted to testing my ability to increase tempo while maintaining grace, ease and efficiency. It's one of the surest ways I know to grow more robust brain circuits.
I posted my latest example at #33 on this thread