EDIT:

Long story Longer and MORE Boring, As we have a renter on our place they were SUPPOSED to be maintaining these fence, are strung pretty thin these days where have little time to do what HAS to be done daily and my fences are showing the distress.  Not belittling the renters as they are working hard but their lack of time to get things done is wearing thin on my own patience.  Texted as to some of their calves getting Out and got a response back that "Your Fence Corner Post are rotted off, fences are sagging so calves are getting out", pretty well pushed the fence work BACK to me.  We do not make a Killing on their rent as does only make property taxes giving us a tax break, do know the prices of beef are still low where expenses are rising fast, but if make a written agreement to tend fence then need to tend fence or stop renting.

They are just trying to make a living I am aware, but have expanded cropland faming, have numerous livestock rental farms, are now into sheep to make better money, farms are scattered across four counties so from morning to deep dark these guys are busting hump just to get numbers counted, feed dispersed, inoculations made, bulls rotated and calves weaned to then be hauled for sale, planting has just opened up from being so wet, got to be hard tours.

On stretching, Have to pull taut, then Wrap wire to tie around Post, cut Chain Links make good weld on closable wire eyes, back wrap wire and as loosens over time those little J Hook tighteners are worth their weight in time saving.

Cousin of mine and wife's boss both use steel at corners, driven not drilled and set in concrete.  Use either cut chain links or nuts and does not matter bolt size welded to pipe.  Gate Pivots holes get pre drilled all way thru in drill press to keep square.  For those post know will have sucker rod braces pre drill before pound into ground, slight oversize hole so can set rod in one post and then slip into the other weld in place.  Or can cut to length and surface weld.