Heading down a slippery, slippery slope

Should you change the definition of promoters, passives and detractors? Or should you stick with the accepted standard?
This question comes up fairly often in our client work. Many Bain clients are international or global companies. It turns out people in various cultures use response scales differently. Some Asian cultures, for example, mostly use the middle of the scale. Some South American cultures use the extremes. Very few Japanese respondents are give a 10, but Brazilians use the top of the scale all the time.
Should the definitions of promoter (9-10), passive (7-8) and detractor (0-6) be adapted to local markets?
Sony did it!
Click on the image to see full sizeIt appears Sony developed custom definitions of promoters, passives and detractors. I ran across this presentation slide from research firm Synovate in 2009. A client (not from Sony) recently sent it to me again when he wanted advice responding to local market pressure for changing the definition. (Guess which country manager argued for custom definitions. If you think it was the head of Brazil or Mexico, think again.)
I wonder if Sony stuck with their custom definitions, or