Therefore don't be surprised that it is inflexible.
Yes, it is.
However not as inflexible as some might have you believe. Yes, potentially you cant move house, and yes there has been one issue in the last 20 odd years getting the A and W flexible friend, but as far as it goes that is really not too bad. Lets face it if you wanted to fly an N reg any where in the world for the last twenty years (or more) then as long as you havent changed address and were prepared to shell out for one trip to the US (or L2K or one of our roving friends from the States) you would have been good to go for the entire time. That is not bad really?
I suspecty if you had kept your CAA / JAA / EASA license up to date over the same period the hassle would have been greater and the cost at least equal.