Continuous swimming workouts

After doing a spinning (i.e. stationary bike) class yesterday I got to wondering if there would be a benefit to training for swimming in a similar manner. So, for those who aren't familiar with spinning classes, they involve cycling continuously for an hour or whatever, varying tempo and resistance, but always keeping the pedals moving, even in the rest segments. The instructor rides along with the class, facing them, and explains what to do. For example, "ok, now we'll do 30 seconds sprint, followed by 20 seconds rest, repeated five times." You get the idea. Obviously most competitve swimmers don't do their workouts quite like this. Yes, we vary the intensity while swimming, but the true rest is done standing at the wall. The logistics to a continuous workout in swimming would be more difficult because everyone's heads would be underwater, but if the technical glitches could be worked out would it be better than the current method? So do you think this would work in swimming? It seems to me it might be especially useful in masters swimming where many of us are under time constraints and need to get our workouts in quickly. Honestly, I don't know if it would be better, worse or the same as the current swimming training philosophy, but it seems like it's at least a good discussion topic :) Lastly, yeah I know there's already a poll thread asking whether we swim continuously or do intervals: forums.usms.org/showthread.php, but this is different. I'm proposing continuous swimming AND intervals.