I couldn't stay in 200m sets any longer and so today I went a little against instructions and set out to do 1000m with my new technique. Despite thinking that I was starting slowly the first few lengths were at CSS pace, although I soon settled into a sustainable rhythm. Towards the end of the set I noted that my stroke was becoming scrappy and this is shown in the figures by a progressive increase in SPL from 21 to 26. I refocussed and managed to finish with a final length of 22 strokes.
Over the first 200m (i.e. my usual warm up) I took 4:54min which is clearly below 5:00 minutes although by no means a PB. That makes sense as I had my mind on the longer task. The 1000m took 25:25mins which is a PB pace of 2:32min/100m. Two seconds less will make a great goal!
Some collation of data:
18/01/18 2:32 min/100m (ie 4% better than a year ago)
05/03/17 2:42 min/100m
06/02/17 2:38 min/100m
04/01/16 3:02 min/100m
26/02/15 4:00 min/100m with pauses (moving pace 3:40min/100m)
Looking back over 3 years it is very clear that I've made substantial progress even though week on week gains seem erratic or negligible.