the catch of the pull and the pull of the catch!

[Zenturtle]

with good swimming technique ingrained in every fiber of your body, swimming 2 min/100 is really low effort.
Much lower than 30 km/h on a bike. For elites more like 15 km/h effort level. almost nothing.
Everybody is possible of making it an 20 km/h effort level with enough practice I guess.
The problem is that older swimmers are such bad learners. We are really really stupid learning new physical skills.