>I hadn't thought about something like you GPS trail example where an instrument produces a series of absolute positions before. Perhaps a measured version of "nosurvey" would be useful, ...
Or maybe a new shotflag "Ignored" to compliment the existing "Duplicate", "Surface", "Approx" and "Splay" flags. "Ignored" would mean the shot does not count for length and depth statistics. Maybe the defaults for all shot datatypes except NoSurvey could be "Not ignored" And the default for NoSurvey could be "Ignored". However the user could explicitly change the state of the "Ignored" flag if their usage does not suit the defaults. This change, while it would change the behaviour of some existing datasets, would bring Therion in line with Survex (if I understand you correctly) and also allow the user flexibility to specifically ignore or not some centreline data. A pain for the Therion authors no doubt. Bruce
