Yes, they are. They are losses accepted in the name of research. They are an investment; there are some things that need clinical tests instead of attempted observations in uncontrolled conditions.
I generally do not do them, but I appreciate those who do.
I sort of agree with you, but I think information gathered in your normal routine would be more valuable. I think in most cases people are "testing" mileage friendy routes to gather data to satisfy ego more than wallet.
I used to curse when I got stuck behind you guys on a two lane blacktop. If you can't beat em?
I don't draft very much but I do find it handy for extending an Interstate coast to a off-ramp. Rather than counting stripes (they vary) I try to set up the "Sight picture" Wayne Gerdes posted on his site.
2000 Ford F-350 Super Cab Pickup
4x2, 6 speed manual
Regeared to 3.08:1
4 inch suspension slam
Aero mods: "Fastback" fairing and rugged air dam and side skirts
Stock MPG: 19
Summer MPG: 27.0
Winter MPG: 24