Good points.I think it is important with youngsters not to tire them out running too many water blinds directly into the wind.
I often start with one long water blind into the wind and call it success and quit. Gradually they get stronger
and stronger with more endurance for big swims, but too much too soon may be counterproductive in terms of fatigue and water attitude. I also use an aquarium thermometer and want the water temperature above 60F...water is typically the warmest in late afternoon.
This mutt is not really a youngster, turning 3 years old in the not too distant future. Endurance shouldn't be much of a problem since she is accustomed to our pond/lake, which has 200 yard swims in just about every direction ... nonetheless, I'll keep an eye on that.
Our water temp around here is rarely too cold for training except December - February, and even then we can have warm spells where the water temp is acceptable. In this area, heat is a bigger issue that cold.
I'm hoping that the wind picks up soon so I can start with the new plan!