i get that..but if you naturally focus on better time over distance it = better avg speed....so the question...I don't get it.

what you mean is...should you focus on putting more hours in the saddle and riding longer distances even if it means riding slow or should you be doing short distances at a faster pace. which I would say: depends on where youre at currently with your riding ability. are you only riding 20 miles consistently? If so you should focus on finishing that distance with a better time/avg speed. If you ride at a decent pace in your 20 miles with a good average then starting upping the distance, then work on that average.