No I do think that agricultural land in the UK is worth more than that. Modern valuation methods that Strutt and Parker would be using would stem from a residual profit making valuation. The same as you would value a pub/restaurant. These methods of valuation do not take into account demand, availability and location etc.
Piston gone I don't think that the area where my strip in Ireland is will be photographed on google earth. but if you pm me i'll send you a picture to your e-mail address. Hows that. I'll even show you my once milking parlour now hangar!