Saddle at the end of the rail ok?
 

I am trying out a different saddle and when I set the same nose to middle of the handlebar position on the new saddle, the seat post clamp is at the very end of the rails. Other than no future forward adjustment short of changing to a different seat post, I don't see any problem with the saddle being at the end of the rails. Still, it just does seem like a good idea for some reason. Any thoughts or experiences?

Pushed forward the saddle rail metal fatigue will take longer than if pushed back ..

because of the way your weight is distributed ..

I think it depends a lot of the make of the saddle and your weight.

I am large/heavy. I broke a saddle last year. I had it pushed back all the way. It turns out there is a spot which it shouldn't go past or it fatigues and dies. The good news is it was a cheap saddle and I could adjust it and ride home (carefully).

Bike saddles support you from the rear where your ischial tuberosities make contact. Bike saddle shapes vary. There is probably more consistency measuring from the rear of the saddle.