Can you train people for white water canoeing without them spending time in white water?  Is training without a realistic setting viable?

I spent six years trying to get people ready for white water canoe poling and paddling by having them complete exercises on smooth water.  But when we got to the actual white water, they seemed barely better off that those without the prior training.

So the question is can you learn something without actually being there doing it under realistic conditions?  I’ve gotten my answer.  What do you think?