Well, never say never.
If the seeing is no good, and it never really is...
The tropics can put up some excellent seeing in modest apertures, anyway. I can regularly get down to 4 waves and sometimes less than one wave prior to final touch up on the first ring itself. (Had to sketch it one night, seeing was awful good...absolutely awful. I mean, inspiring awful.)
Really, though, it might be 7 of 10 is sufficiently good seeing in-focus with patients, but 8/10 and better allow for very close to focus inspection without the Poisson spot jumping all over the place and the first bright ring closing in on it.
Otherwise I totally agree with you, use a star in focus when seeing permits. If not, nothing wrong with a web cam and some free software (thanks Frank.) There is a certain beauty to a well collimated star image with an equally bright ring and a certain confidence you're getting the most your scope can offer especially when seeing cooperates, too.