I'm probably more concerned about the depth of the cut based on the drought conditions that we've had here in New Hampshire for the last 8 to 10 weeks, lolI'm currently at 2" on my last cut, going down a half inch over the last few cuts in preparation for seeding. I may keep it at 2" for my next cut versus 1 .5", but with good weather coming around for tall fescue, I actually want some of the good grass right now to be a little delayed in regrowth to allow sunlight to get to the new seed. The crowns won't be affected at 1.5 or 2, but may leave it at 2 now.
I know that I cut my lawn way down about 12 weeks ago because I knew I was leaving for a long weekend down South and didn't want it to get too out of control while I was gone. As luck would have it we rolled into these drought conditions which fried my lawn. I guess the only good part of it was I didn't have to mow it for almost a month because it was just about dead. Since I've been able to get it recovered on the existing part I'm cutting it 3 and a 1/2 inches or so and letting it get nice and plush.