Says all the planes landed gear up....
Takes more than a hour or two to trip up a student, and for the RG aspect that's what you need, get him on short finial, call out go-around, then point to the gear selector.
Plus being able to really use the CS and cowl flaps vs just operate it, that a couple hours.
So yeah, Id quote 5hrs, if the dude picks it up in 3 cool, but Id wager it would be closer to 5. Many insurance companies have that 5-10hr dual requirement based on years after years of constant stats.
Here is a good one
http://m.youtube.com/watch?v=5McECUtM8fw
Here is a better one
http://m.youtube.com/watch?v=ObLQnY5fDU8
I run my flows, confirm with my checklist, then I have my short final sight picture where I run a final GUMPS check. Run all checks aloud, and touch everything you're checking.