Cze,
No offense to you but I would like to see some proof, if at all possible, to back up your claims.
Can you be more specific? What periods did you run "way above 150mpw". Also, I am sure you are aware 5000 per year is 104 average which quite different than averaging 120-150 for a full year.
Also, what, if any tempo/AT threshold runs did you do? And, what are your PRs and Age?
If you don't do threshold/tempo runs and you slog along at 9-10 min pace, then yes of course you will never be 2:10 quality.
-Soup