I have been mowing for this older lady for 8 years now, she recently had her brother in law start helping her out with things around the house since she is getting older. she called me earlier and told me to re-install the fence because her brother in law said the way I have it will cause the fence to sag. What I do is unbolt the chain link and roll it back so I can get a big WB in there and use a length of chain and a quick connect to hook it back when I leave. I have done this on many yards over the years with no problems. Well Im not doing her yard with a 21",If it was going to sag it would have done so by now, but she doesnt want to start any trouble with him. I think I may try talking to him directly and tell him the situation and if hes got a problem, he can start mowing it! This is a wonderful trick but you cannot pull the fence as tight as it was with the bolts so there is a small gap but not even a small dog can get thru it. I have evn tried rachet strap to pull it tight and that doesnt work, they must use a special fence stretcher?