Mike also gave it a shot and here is his words on it.
mrennie wrote: This'll sort the men from the boys.
This is very hard!
Succeeded at the fourth attempt! 5mph coming over the crest of the hill. You really do have to be on the ball with this one, watching the throttle, cut-off, fire and water all the time (I was almost getting dizzy flicking back and forwards between the two sides of the cab!). Then there's the downhill part - got to be very accurate setting the brakes and anticipate the right moment to release them before passing from the 20mph zone to the 40mph stretch. It's a really good test of skill.
And here is the file in case anyone would like to try. (It's doable with auto-fireman.)
http://steamcommunity.com/sharedfiles/f ... =223847350