Very lucky here to have the space, and appropriately placed trees, to allow me to put up a full size dipole for 80m. By all reports it works very well. This week, prompted by VK3LRJ, I tested the antenna and found that resonance had moved down quite significantly.
The weekly club net is on 3685 so that's quite a bit away from where the antenna is now. I pulled it down, cut off a bit and folded back the ends. I think I shortened it by about 500m.
Much better! The 7300's built-in tuner has no trouble but it's good to not suffer the losses in the tuner if possible.
The wire I'm using is figure-8 speaker wire split so I guess it stretches quite a bit. So far it looks to be in good shape but I don't expect it to last forever.