Being a tire fanatic I rotate every 5k miles - all vehicles, all the time. Only difference is where I move the tires. On the Accord and Civic, I just do a front to back rotation. On the Pilot, I do a "modified X" pattern - front to rear, rears crossed to front. On most cars these days, you start to pick up a "feathering" of the outer tread on the front tires (FWD is the primary culprit, which includes all Hondas except the S2000). So while the tread depth might not get impacted, the wear and long-term "usability" will - so rotation every 5k miles is essential.