As usual you are half correct and ( like a number of impecunious southern europan governments) pushing the agenda that you favour by only quoting part of the regulations.
I also think that you are probably correct about the EC member states getting tough on those evading tax but it will be much more difficult for them to try to tax me if I am already paying tax in my EU state of residence. I can't help thinking that if the tax is split between two or three EU states it will cost more to administer than the money they collect !
While I can't get the link that you have posted to download I suspect that it is not an official government website so I will direct you to the UK government website on the subject, please note the second and third paragraphs.
HM Revenue & Customs: National Insurance: New EU rules for flight and cabin crew working in two or more Member States
As to the income tax I find myself in agreement with Binder.