"Back in the day", when Delta started up Delta Express (anyone remember that?) and the pilots were on a lower pay scale, there were second officers who had NEVER flown either captain, or copilot on a Delta jet who up-graded directly to captain on the express operation.

Many wise people predicted dired consequences, but everyone did just fine. Anyone Delta hires has the experience and ability to be trained to fly captain day one.

Never underestimate pilots' survival instincts....