Originally Posted by
subgrade
That must be a first when I hear of someone stepping over the top tube on a diamond frame, instead of swinging the leg over the rear wheel

Yea shouldn't it be the same as getting on a horse?
Quick note if he has a hard time lifting is leg that high have him stand further from the left side of the bike and lean it towards him. This will lower the height and then you straighten it up right as you move to your right.
Not sure If I worded that correctly but I remember that is how I used to get on a ten speed road bike when I was a kid and a 26 inch bike was to big for me to get on just by lifting my leg over it.