LOL @ Roy you tossa
I don't know how to get the proper graphics used on here but I'll try.
OK, /o is read over crest, it's normally adjacent to something like an /o into or R4/o, whatever.
oo/ is read and I like read as striaght over crest, flat crest can be a little dangerous and misleading. Some guys say "flat over crest" but that can end in tears.
Typically during recce we look at it, and if it's safe, then we say "flat over crest", and make a note on the notes like, FLAT, GO!!!, and the Nav will say again, "yes it's flat" if he has time.
For instance on say, South Rianna stage, there's some long straits with blind crests, and they are indeed flat in 5th (with a little lift to settle the car for landing), but later in the stage there's oo/ then (then being about 100m) into L3, so you don't want to be flat. Thats the time the nav needs to be well aware and reading those notes together, and they should be underlined to ensure that they are.
I hope thats not confusing, I have trouble explaining things without my hands! lolol
Edit: And it doesn't reference the shape of the crest, ie, yump or jump, it's purely the direction of the road.