Where's the "Best Place" to go Looting the Archaeological Record preserved under Grassland?

On a metal detecting forum near you, member "rob-greaves' (Sat Jun 11, 2016 10:14 pm) asks: 'Pasture: Edges or middle more productive?' :

Here's a question that will probably get a few differing responses...  When detecting large pasture fields, are the majority of decent finds found around the perimeter - hedgelines etc. or away and in the central parts of the field? Considerations like people that walked on the land previously - where were they going? Crossing fields or walking along established tracks and paths?

I do not expect there are many readers of this weblog who know what's what who'll be holding their breath until this question gets the response it requires. Or until even a small proportion of the metal detector using artefact pocketers of Great Britain learn a little bit of best practice.

What do you reckon? Are PAS records detailed enough for them to give an answer to that question to help their "partners" find more things? Mr Reavill?

Note though that if sites are exploited in a way which is geared to get the most good stuff pocketed in as short a time as possible according to some pre-ordained scheme (e.g., "just round the field edges") no matter how detailed the findspots of the selection reported, they bear no relation to the actual distribution of archaeological evidence across that site. The "data" which get into the PAS database are about individual collectors, not about the sites they pocket artefacts from for personal entertainment and profit. 

Vignette: where the crock o'gold will be.