Personally, I found "shavettes" to be very difficult to use. They didn't help me learn straight shaving. But others will have the opposite experience. My point is, don't automatically think that is the best way to start. If it doesn't work for you then so be it.
I think learning with a DE first can be a good idea. Many of the things you learn will be directly applicable the straight razor shaving and you will not need to deal with the extra stuff that straight razors bring into the mix until the basics are second nature.
I think the one piece of advice that might help the most to start with is "use a light touch". That is, let the sharpness of the blade do the work. If you think you need to force things what you really need to do is think about all the techniques you can read up on here at B&B (and elsewhere). Pressing down harder is never the answer.
Somebody's nuts. I don't know whether it's me or them, but somebody is definitely nuts. I just wished I knew, so I'd know, you know?