Comment 4 for bug 407585

iGEL, I'm using a non English keyboard layout, and only by enabling this option am I able to input using my session (and system) locale. With the option disabled, it reverts to a default en_US. So the option makes sense enabled.

As for suggesting users use the gconf-editors, the tool isn't geared to non techies, while changing the session layout back to an en_US is common for lambda users that learnt to use their own language input with an en_US keyboard (in their home country for example) but are now using a different layout, one corresponding to the foreign language of the country they're in. Some substitutions are possible for simple IM like pinyin, but more complex ones (character based) depend heavily on learnt habits that wouldn't easily translate into another layout (for those people).