Wellllll... averaging the responses and throwing out the 'sports' in the data, (to support my personal bias) I pretty much agree that:

- noglider's post gives us these reference acronyms: TCS = Ego Booster, MA=Pacer, EEA=Route and Partner Planner.

- A app or computer will throw out full-stop time, so fast hard stops and huge jump off the line at lights can keep your average more accurate and provide great exercise.

- Displaying the average speed can be a 'pacer' (do I have that right?). Never drop below average and always try to make it go up on the ride. Great way to torture yourself.

- Requires pretty average terrain, short hills no huge speed increase or decrease.

- Useful when your computer doesn't calculate expected mile lap times weighted by the slope you are on. We only wish...

- Isn't useful like a HRM for exercise.

- Creates one of the more entertaining and friendly sparring on threads.

I use computer and Endomondo average as a pacer and baseline because I have roughly the same exercise routes on average terrain and an average number of required stops, and will eventually show trends in a scatter plot of average speed vs distance. But this is useless unless I spend less time here and more on my bike.