I guess I would say a couple of things.
One, as I said before, I am not a francophone. If this is how francophones feel about the issue, then obviously their opinion is worth more. Since French is their first language, I think their opinion should weigh more.
The other thing I want to say is that when I was learning Braille, I didn't find it an extra burden or an extra handicap. It was like a sighted student learning print. I don't really remember the process, to be honest. I just know that when I was very little, I couldn't read, and then I could read. So it wasn't a struggle.
The other thing is that the English and French codes are different regardless. I understand what you're saying about Nemeth and Antoine, but even just the abbreviations in the literary code are not the same from English to French. Anybody who's going to learn braille abrégé in both languages is going to learn completely different symbols. I know a completely different set of abbreviations for both French and English. The symbols are similar, but they represent different things in each writing system.
I just wanted to make those comments. I'm not trying to say something one way or the other; I'm just telling you that this has been my experience as a Braille reader.