I was at RAFC and then at Leeming when some bright spark invented the idea of 300KIAS LL Nav in the JP5. It bounced around in turbulence, the controls were heavier, it drank fuel, it quickly lost speed in a 60°AoB turn - and if you applied the normal technique for making good a late time at a turning point, you exceeded max continuous limits.
OK, it was fun - but what a waste of time and little training benefit over normal 240KIAS / 250ft LL nav.
A-10s flying at low level would obligingly announce themselves on UHF on the rent-a-bounce frequency, otherwise know as 'low level common'... Shortly after GW1, on one fine day I even had a go at a pair in the Vale of Evesham in a Bulldog - they honoured the threat and after a counter, went on their way. "Were you over there?", I asked. "Sure was - an' you?" came the reply - "Yes, but not in one of these things!", was my response.
Once TWU trained, it doesn't take much for the horns to come out...
