Hi,
For me, the system over-estimates the CSS.
Even if swims in sea, lake is different to swimming-pool ; the topic is the estimation of CSS based on trainings where we work with fins, pullboy and armfins (not sure of the word).
An idea could be to introduce an accessory column to integrate it smartly in the computation.
Per example, i swim in Z2 between 1:50-2:00 where my Z2 with pullboy is between 1:45-55 and with full accessories between 1:40-50 ! Where my CSS is 1:40 lol !
I don’t know if the watch description is the same for all watches ; garmin is very complete including fins etc. So, it could be store during the exercice. In the analysis, the user could tick/untick if he has not used it. Per example, after a long ride, i prefer to add pullboy for swim the same day even if i keep the proposed training.