Increasingly, the brace position is demonstrated by carriers that use video demo. I have seen long haul do this with VS using cartoons and Thom using children (brilliantly if I may say as then children on their predominantly holiday business model more likely to watch).
Whenever I see such videos or look at the card - I am sceptical that I can make it work in Y. I'm of average height and build but have noted over time in these forums that feet position and flying debris are critical and I suppose that I shall try to concentrate on those, even if I cannot get my head further down.