Bridge
Why do you believe this is your last chance to apply? I was of the understanding that you have until the age of 26 to be able to enter IOT as a pilot, so being 23 still gives you plenty of time to have another go if you are unsuccessful this time. Or have you been told otherwise?
On the matter of people leaving, Pontius is right on the money - they are leaving because they have had their fair share of action, and little chance to rest. The enthusiasm wears off after a while, and outlook on life and what's important changes. Some people can keep going, some feel that their time to leave has come. It takes all sorts, and most importantly, it's your sort - the young and enthusiastic type - which is important to maintain the 'balance'. It's not all bad in the service, people have always left, it just looks bad because there are less of us around these days.
So good luck with the application, mine is in to cross to the dark side at the moment and I would jump at the chance to have a 'weak recommendation' because at least it's not a no (of which I've had a couple!!).
Fingers crossed
MB