The 20% rule

[Fiona]

My hubby's first horse was a TB who had raced over fences and p to p until he was 11 (raced about 30 times including in the summer - harder ground??). He went on to be an intermediate eventer and was completely sound up to about 20 when he semi retired to be a (rather lunatic) hack... He's definitely what you would call a 'high mileage' horse...

Fiona

 

[MileAMinute]

I wouldn't trust a vet to advise on weight, whatsoever.
A well respected vet in my area suggested my OH could ride my 13.3hh Welsh X pony (in walk). He was 14 stone at the time. The most I let him do was longline or lunge. He didn't go near a saddle!

 

[alainax]

My horse gets weighed for the first time on Saturday, I am looking forward to seeing if my guesstimate was correct, or a mile out!

I agree that there are so many other variables to take into consideration, and plain decent horse sense trumps all rules. That being said, sometimes a clear cut off is helpful for those who are not sure.