[Wavytone]

LOL... You should get a job in the marketing dept of Celestron, who published a technical paper proposing it was sufficient to put 90% of the light within a "circle of confusion", and carefully avoided actually defining the diameter of that "circle of confusion". Mel Bartels “less than perfect” is not defined, and it sounds suspiciously like someone with a fast newtonian trying to justify a big fat secondary obstruction.