. Hedgehog will back this up at the Roman Fort of Castle Collen near Llandrindod Wells where the site of a vicus was not believed even though Steve had been finding stuff for ages. The archies took a lot of convincing. Hedgehog could tell you how much grief he had in this.
It all turned out right in the end, they looked at the site with ground radar equipment (which they got funding for because of the finds) but didn't tell me they were doing it, if they had I would have shown them where the temple was as well!
Because it was an extension of a site that had been previously scheduled, then they would not schedule the area (all new scheduled sites had to be previously unrecorded sites on "new ground" and that probably still applies.)
I will say that whoever set the scheduled area in the first place did a very poor job of it (many moons ago) and the line of the scheduled area only took in half of the bath house.
You would think with this in mind that finds would come out by the bucket full, but it wasn't the case, on average it would take about 4 hours of detecting to find anything Roman, the fields had been ploughed during the war and not touched since , so I would guess the majority of artefacts would be out of detecting depth!