Kaleb, I am confused, are we giving them more techs regardless of whether they get Oracle or not?
If they miss Oracle, they will basically get Writing "free" from us.
If they get something other than Feudalism with Oracle, they will give that instead of Feudalism (ie if it becomes obvious another team is likely to get Oracle before them, they won't be able to wait until Monarchy is teched)
So there is a risk we will do less well out of the deal in the (unlikely) event that someone else beats them to Oracle. But on the whole, I think this is a risk worth taking, as Cav will not let the deal through if we only put the last tech on condition of them getting Oracle first. The feel that this means we are leaving them to shoulder all the burden of risk involved in building the wonder and that we aren't really intersted in partnership of equals.
They are being so generous in giving us Feudalism without asking much in return because they recognise that we are also risking something in taking the gambit with them.