Today I was at Askern with @CoachMorg. The initial video showed that my stroke was more relaxed than previously and I had some degree of elbow bend in the catch. However my hand entry was still leading into a dropped elbow and raised hand. We spent a while working on dropping my fingers to gain an early catch and tend to raise my elbow at the same time. Naturally this leads to a reduced reach.
Next we looked at stoke rate. We did the ramp test from my leisurely turnover of 56spm to a tough 70spm. There didn't seem to be an obvious dead-spot glide but it was clear that an increase to 62spm would give a distinct increase in pace with only marginal increase in effort. Notably, at the highest rate it looked as though I might crack 2:00min/100m if I could sustain it. That would be great.
Anyway, the plan is to work on 100m sets at 62spm and then lengthen the sets until that rate of arm turnover is natural. Then increase the rate a little! It felt far simpler to focus on stroke rate than my previous attempts at CSS lengths, Morg described that focussing on process of stroke is far simpler and immediate than thinking about an outcome such as pace.
The only problem is that my TempoTrainer seems to have perpetually flat batteries despite replacing them.