So why don't CAA qualified Air Traffic Controllers get some dispensation towards the ATPLs as well?
I did Aviation Law to a far higher degree than the ATPL requires, met theory, met practical and navigation subjects to at least ATPL standard and several other subjects to boot and got zilch in the way of exemptions when I came to do my professional pilot exams. These were CAA tested exams and were long hand as well, long before the days of 'the answer is somewhere on the paper'.
One rule for some and not for others.