It has happened before. In the mid '60s there were cutbacks, and an edict went out to the FTSs. Any students who had taken more that 'n' Flex hours (not sure how many) were to be chopped, unless their Flight Commander could guarantee that they would graduate 'above average.'
As a result, one of my old friends was scrubbed from his Jet Provost course. Ironically, it might have saved his life. He became a Fighter Controller and collapsed one night over his radar screen. The Docs discovered that he had Type 1 Diabetes.