PPT - err, I guess that'd be the lack of hours ?
Night_fr8 - It's all very well doing 350 hours per annum but only when you've got several thousand hours already in your log book. When you're new to professional aviation what you need is 'hours'... as that's what unlocks your (f)ATPL and it's 'hours' that get you the experience you need to get a command.
And, fwiw, I believe it's the case that Rob / PPT has a good few thousand hours on the B757 (as do I)