The law is different here in the United States, of course, and in most countries. I wonder how much of the slow economic growth and high unemployment in France is connected to this information-denying and thus efficiency-frustrating law?
It can't help, but it's hard to imagine that's anywhere near the top of France's legislative issues.
On a more general note, I would to reconsider your appreciation about France, and in general, about countries which work differently from yours. Unemployment in France is a huge social impediment, but I don't believe it has nearly as much effects on the economy as you think it has.
One of the reasons for it is that jobless people are low-productivity, low-qualification which, if employed, would not contribute significantly to our economy. Also by increasing work price, pressure is created on companies to improve work efficiency. I wouldn't say there is a strong connection, but UK's productivity puzzle has been conjectured to be linked with zero-hour jobs.
A lot of people agree that our main problem is that our managers are shit while our engineers are ok.