Xcode 4 - key binding option key, possible for you?

In xcode 4, I can't bind the command "Shift Right" to option+tab key and "Shift left" to option+shift+tab. I'm using textmate and those commands are binded like this, so I would like the same setup in xcode 4... But for some reason, it adds the command key in my bind! so option+tab is replaced by option+command+tab.

A quick fix that I found was to overwrite the bind in the system preferences, but was wondering why Xcode won't let me use my bind?开发者_如何转开发

Only the developers can say for sure, but it likely has to do with the many meanings of the Tab key:

• generates a tab character
• used with command to switch between applications
• iterates over controls in windows and dialog boxes
• iterates over links in web browser

I think I missed a couple, too. Due to its size and position, the Tab key is a hot commodity. The specific combination you want to use probably conflicts with an established or planned use of Tab.