The point that is being missed here is that absolute weight is very important (both min and max). This is because the ejection seats that we use have qiute stringent limits. I can't remember the exact limits off the top of my head (don't tell Staneval) but 15 stone is too heavy - certainly for the Tornado. This doesn't mean that you couldn't fly in it at all (people regularly do) but it isn't a zero zero seat. The RAF therefore doesn't like people starting off with this limitation. However, like eye sight, people who have 'deteriorated' just continue flying with the new limitations. This may not be a problem in the multi/rotary world but again the RAF doesn't like people being limited in their posting right from the start.
This might seem quite negative but I think the one huge positive point is that the RAF is desperate for aircrew and will overlook minor discrepancies for the right candidate.