Hope you don't mind a non-instructor sticking his nose in here.
It's my opinion that any student who can fly perfectly well with foggles on, but looses it when taken into real IMC, has been cheating, and peaking around the foggles.
I base this on my personal experience. I refuse to cheat - the only person I'd be cheating is myself. When I put the foggles on, I don't look up. Simple.
During my PPL training, I did the obligatory 180-degree turn, and a couple of other simple manoevres, under the foggles. I then got a chance to fly in real IMC briefly during a later lesson, and found it no harder than flying in VMC wearing foggles.
Around 150 hours later, I did a cross-channel checkout, which happened to be in IMC for about 1/2 the trip. I had done no instrument flying since my PPL training, and was a little nervous about doing a flight of this length in IMC. The instructor gave me the chance to cancel, but I decided to go for it. I flew the whole way, and I let the instructor navigate during the portion of the flight which was in IMC. I did lose control once... that was when I looked away from the instruments to look up some morse code on my knee-board. Apart from that, I had no problem keeping straight+level and making rate 1 turns.
I'm not an exceptional pilot. If I can manage to fly from White Waltham to the south coast on instruments, in real IMC, having had no training except for the tiny amount that's required for the PPL, then anyone can do it - especially after compleating an IMC course. The only difference between me and other students is that I didn't look out of the window when I had the foggles on. In fact, on that trip to France, at one point my instructor commented that it had started raining. I glanced up at the windscreen and saw that she was right, it was raining - I simply hadn't noticed because my eyes had been glued to the instruments.
FFF
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