This practice set has become a fav for me and in reading many posts I can imagine it being applied to help or facilitate one's practice.
It's a simple pyramid I borrowed from one of Terry's blogs. The intervals/distances can be altered obviously as well as the intent and repeated over time can be a useful, organized way to practice that certain something; drilling, drilling to WS, pace, catch, 2bk, or the voodoo in you.
The set: 4x25, 4x50, 4x75, 4x100, 4x125, 4x125, 4x100, 4x75, 4x50, 4x25
I believe the 'original' intent was to breathe every three holding the same spl on all working on a sustainable cruise pace. Interval time: :25 per 25yd.
In yesterday's practice I used an interval of :30 per 25yd (as a 'warm up') on the way up and :25 per 25yd on the way down. Breathed every 3 on the 25s, 2R 2L on the 50s, 3R 3L on the 75s, 4R 4L on 100s, and R one length L one length on the 125s. A solid minutes rest then back down.
The 4x allows more opportunity to capture the feeling or 'sense' I'm looking for and helps in carrying it over as the distance increases actually allowing me to better settle into a rhythm, striving to not add effort but become more aware of how I can do it easier; always easier.
I think I had a good practice not exceeding 15 spl and beginning each 'block' at 12-13 spl. 25yd average :20, 50yd :40, 75yd 1:00, 100yd 1:28, 125yd 1:50.
I did find it harder however to lower spl on the way down but did not let it distract me just made note. On the back 25s I was at 14 spl but still :20 so after the set I intentionally 'stretched' out until I made the 12 with little effort. I'm aware the spl will increase over time and distance so the 14 on the end I think is a good thing.
A fun and challenging practice over all, hope you try it.