Yes in this photo taken in the early hours of the 4th, we can see that a small child wishing to gain a better view of the restaurant table, might gain a good increase in height by standing on the wall at the base of the railings. I have not measured this wall yet but I guess it may be about 300mm? A further approx 50mm could be gained by standing on the lower horizontal metal rail of the railings just above the wall - zoom in to see this. (Source: Vol 1 Page 21)
I get what you are saying, but did you realise that is the wrong railing? The railing you show is not immediately outside the sitting room patio windows but outside the patio windows to Kate and Gerrys bedroom.
Madeleine would have gone straight to the closest railing and not that one imo.
Anyway, I really do not think that Madeleine came out via the patio doors.
Btw, do you have a definite answer to this. Are you technical, Pegasus? Is the sitting room patio door top hung or bottom supported.? Please.