This the type of session I like to use mid-season especially around the Christmas holidays. The format is one that I like these days as it means a change every 500-600 meters or so. It keeps things interesting and stops it becoming a slog. The set also incorporates a little bit of speed and some backstroke to balance out my shoulders.
As usual I must point out that these are my sessions that I swim, people are free to try them and adapt them, but do so at their own risk (i.e. don’t blame me if anything goes wrong).