I seem to remember doing the same at Knaptoft (didn't 'fess on the earlier thread either, as was too busy being entertained by others much worse than mine) only it was the second last fence, so I jumped the last and got a big E. See, there are always others worse off than you.
The rest sounds fab though, although he does look like he needs something bigger in all respects to get his teeth into. I think horses over 17hh should only have to go in a 20 x 60, never in a 20 x 40.