I recently overheard an increasingly irate glider pilot and ATCO having a discussion about the glider's whereabouts on the Benson frequency. He (the pilot) was a bit lost and was just warning her that he might brush the corner of her (the controller's) zone. Five minutes later, he was still explaining that he can't guarantee a heading or level, while she was still trying to explain to him that she needed to know where he was which is why he needed to do a left turn for identification...
I felt as I left the frequency that they were destined to keep that going for some time...
He might have got away unnoticed if he'd kept quiet, I suspect, but that doesn't seem a good idea - I reckoned he was already in the zone.