A question to those using time rating.

I gave it away some time ago as I just couldn't make it work.
I used only on shorter distances as per common wisdom.

Never having changed any of the algorithm I use, I started to try it again on distances over 1600M a few month ago and to my surprise it performs exceedingly well.
What have I done wrong-right? Or is the short distance belief just a myth?
Similar experience anyone, or is it just an ephemeral fluke?