One further thought

Really I can justify a few good long swims as part of my training this fall for the 5K sea swim. It would be more fun to do a version of that workout with a bunch of lanemates of similar speed, then one is more likely to stay on the clock; and it is too crowded at open lap swim hours to do that sort of workout, so really there is no easy way for me to get the full amount of time I would need for the long version. But even if I had just a 60-minute slot and a lane more or less to myself or split, I could do a nice modified version of that workout, just doing the 800 warmup and then going straight into the 100s and only going up to 3 x instead of 4 x for a total of 3200, that would fit into an hour as long as I started promptly...