I'm just in the process of going up to noble (again), and decided to give the strategy a go today. It worked pretty well in the beginning. But I made some poor decisions with city placement, which dragged me down financially and made me suffer through a looong period of low science (~20%). I attached the saved game with my current position in case you want to have a look.
I founded my first city to the west, so it could work all land and get the corn (this turned out to be a lucky place, as the site also has iron and coal). I then discovered copper further to west, along with marble and pig...since I saw no other metal close then, I decided to found a city there. And then I made the first set of mistakes, founding another city south of the copper to get hold of some spices, and YET another to deny De'Gaulle the horses. These two cities cost me a lot (distance maintenance). Maybe they kept the french from becoming too strong in the long run, but for the time I was crippled economically and couldn't continue settling the nice area east of my capital.
In the other regards, the strategy of focusing on units worked very well. As you can see in the power chart, I kept up ok...however, I never put my army to use, which probably was the next mistake I made. I now think I could've got some gold from capturing (and razing) the french cities. On the other hand, we mostly had tech parity, with De'Gaulle always having a slight lead militarily...he had catapults when I didn't yet. So it might have been risky.
How to proceed from this point? I am not certain. De'Gaulle just got Infantry, and with the large stack in his northern city I don't think my (now outdated) troops could do much. I am on good terms with Cathy, but knowing her I fear for a backstab attack...she must've got cossacks, and lots of them, looking at the power graph. The other leaders are probably ok.
I think I'll attempt a space victory. I'm not tech leader, but also not much behind. I have some good cities (I need to go over the tile improvements, don't tell me

and with focus on space techs I should be able to win.