ah, ok...
I figured after doing nearly 1000 miles now on the fixed it might be something technical.
If its just a technique thing, I'll have to practice.
Of course, at lower RPMS its easy to believe you are in fact pedalling in "circles", but at higher RPM's, that assumption is obviously wrong in my case, and possibly many others who believe they are achieving a perfectly circular pedal stroke.
Of course, i suffered at 100 RPM before, but 140 + is kinda quick don't ya think ?
people have told me 200 RPM is possible in short bursts, but i've also been told to watch for slowing down from such an effort. As i'm unlikely to reach such high spin speeds just yet, I'll have to take their word for it.