Jason, not being a rower, i was priming myself for the rowers among you to tell me this is old-hat in rowing circles!
I presume the difference in stroke rate is related to the fact that there are six crew in the boat, which is around 20' long, 6' wide and at least 3' deep, made of timber planking, real old-school, and must weigh 100s of kilos. Each oar is double an average persons' height, and heavy timber as well.
An observation from setting the task to groups of clients-
Those who can blitz a 250m or 500m balls-out sprint, don't often do as well with the 1k as described above; i dunno, maybe it's that inability to divorce decreased stroke rate from decreased power in the brain.
Mat, unfortunately these guys and girls (5 girls, 1 guy) don't respond too well to receiving suggestions outside what they already do.
When in the weights room, it's 20kg Smith machine squats, lat pulldowns, seated rows, and bicep curls
and this is after asking me for some advice on supplementary exercises, to which i offered DLs, power cleans, real squats, and pullups.
I guess they know better, because, hey; they're the rowers, not me...