I suppose that's the rub. Undoubtedly, if you took home £10,000+ in a month, ones gross salary in the UK is very handsome. The tax regime is so incredibly punitive, it's pretty hard to capitalise and generate wealth over and above a certain level; which, these days, is quite low.
Am I remembering rightly that the IR seemed to create/change legislation in such a way that it seemed like it was exclusively targeting flight crew commuters who were able to previously minimise their UK tax exposure whilst working for UK Airlines?