In the end, if the shows duration is 1800 and the recording comes up short - 1793, “clean”:false but there’s no error. In tablo’s [web] app it doesn’t report and issue with it. I think I’d have to look at the root - read only log directory to follow which tuners were in use. I’m not going to do that.
Just because it’s “dirty” …tablo’s app don’t seem to report it as bad, I presume, if there’s no error. I suspect it trimmed the few seconds to use the tuner.
I am learning to find the naming templates useful. The the point -n- click is beatiful. It’s really handy for the occasionally recorded shows I don’t have something set up for already. 
thanks!