Fully agree Ronnie , that's why allowing S/R is a bad idea , if you have to use it then of corse a compulsory pits in should be enforced, trouble is there can often be doubt followed by too much post race debate over who was at fault .
Strange you should say that as a compulsory stop and only one Shift/R is what is being applied in the Privateers.
In general we are a PRO league but the exception is the 'learner' division(s) ie Novices (and Privateers to a lesser degree). We need to encourage those coming up through the ranks and the Shift/R options on offer do mean there is a penalty to be had in the Stop and Go factor.
In theory GPL will not let you respawn until the track is clear but this doesn't always work in practice, so common sense needs to be applied ie wait until you can hear the track is clear, don't immediately Sh/R if you were in a queue of traffic etc. Actual track rejoins are addressed per the guidelines
here.
shift R is not something I am looking forward to when the season starts
Anyone who prefers PRO does, of course, have the option of joining the higher 65/67 leagues ie Amateurs and Works.