The fact you can list some scenarios where it isn't of practical use doesn't mean anything.
No, you misunderstand me. I'm saying that the scenarios where it
is of practical use are rare in UK weather conditions.
How about when the cloudbase is 2000' for your departure and 2000' for your arrival but is lower somewhere enroute.
Quite true. My point was that such occasions (where you can
virtually guarantee cloud base above MSA at the destination, but where it's known to be below en route) are much less common than those where the cloud base at the destination may also be below MSA.
More important, this sort of rating would encourage pilots to set out on journeys that they may not be able safely to complete.
One of the factors that makes IMC flight
potentially significantly more dangerous than VMC (in sight of the ground) flight is the fact that you can't see what's below you. You don't get the immediate warning that you should turn back. You rely on forecasts and judgement to, well, guess if it's safe to complete your journey. Without the safety net of an instrument approach to descend through cloud, personally I think IMC flight (or VFR on top) is substantially more risky than VMC. We don't need these extra risks, but we've got a solution: it's the IMC Rating.