Kedrosky on “laissez-faire” versus “laisser faire”

Economist Paul Kedrosky (the other Paul K.) weighed in today on which French verb form we should really be using “laisser faire” or “laissez-faire.” I agree with his logic, but adding that level of complexity goes against the “borrowed words” tradition. At what point does franglais (or Spanglish, etc.) become English? In common speech, the rules of the parent language are often quickly abandoned (see “datum”), but academics and other high-falutin’ folks tend to follow the rules of the parent language. What about publishing people, who fall somewhere in the middle, promoting good use of our language but not putting it on a pedestal?

I think I’m sticking with “lassez-faire.”

Style note: Merriam-Webster uses a hyphen in both noun and adjective forms of “laissez-faire.”