I agree you want the header cut out ideally, but even with a challenge its always possible you might get a flick on... To not be in position in case this happens is the worst of the lot for me as it's entirely within your control. You don't just assuming your mate will win the ball, largely the whole point of defending is positioning yourself in case the ball runs through and you're there to deal with it.
I agree with all you have said no doubt ..... Even if there is a challenge you should always anticipate your man will lose that challenge and all ready be starting to make grounds on clearing that second ball up and we didn't. But at any level of football when a keeper launches the ball into your half, your CB has got to clean everything up - ball, man the lot, Toby was nowhere to be seen and while it's all "if's and but's" It was something from a Sunday morning defence-wise. Totally fucked off to be honest as i actually now expect us to take points from these grounds, unlike a few seasons ago - when i was happy if we only lost 1 or 2 nil. As good as we have been at not conceding over the last two seasons - i do feel we have difficulty aerially at the back.