>General Running>Heart rate monitor training
Tougher than most, dumber than the rest. "You can not count the miles until you feel them" TVZ
A Dance with Monkeys
the Low Heart Rate training group.
I'm running somewhere tomorrow. It's going to be beautiful. I can't wait.
I don't know that you'll NEVER get faster, but the theory is that it's too much unnecessary stress.
A study came out a few months ago, showing that folks with lots of easy mileage and 1-2 speed sessions per week tended to improve in speed more than those doing harder runs. You can poke around for the news item on Runner's World, or if I remember, I'll do it.
Both Hal Higdon and Jack Daniels have a fair amount to say on the topic, also. Hal Higdon has his own website - to get Jack Daniels' words, you'll have to pick up his book on training - VERY worth it.
My Little Pal