Here's a nice quick set of aliases that allows you to bind a key to turn Turbo Lock on and off, and have a key that acts like normal turbo when TL is off, and stops turboing while held down if it's on.

Bind a TurboLock as the toggler, and +XTurbo where you'd normally have the turbo key (I use spacebar, many people use tab).

alias TurboLock "TurboLockOn"
alias TurboLockOn "+Turbo; XTurboHalt; alias TurboLock TurboLockOff"
alias TurboLockOff "+Turbo 0; XTurboNormal; alias TurboLock TurboLockOn"
alias +HaltTurbo "+Turbo 0"
alias -HaltTurbo "+Turbo"
alias +XTurbo "+Turbo"
alias -XTurbo "+Turbo 0"
alias XTurboNormal "alias +XTurbo +Turbo; alias -XTurbo '+Turbo 0'"
alias XTurboHalt "alias +XTurbo +HaltTurbo; alias -XTurbo -HaltTurbo"

Wow, thats um, needlessly confuseing.

I have two turbo keys, tab is normal, and ] is on\off

alias turbo-on "+turbo ; echo 'Turbo activated' ; bind ] turbo-off"
alias turbo-off "+turbo stop ; echo 'Turbo Deactivated' ; bind ] turbo-on"

That'll toggle, but it won't change your normal turbo key into an anti-turbo key while turbo is locked on. Try my aliases and check it out. My aliases work really well for bot distracting, as, in my case for example, I'd lock turbo on with ";" then press space (which is my normal turbo key, bound to +XTurbo) when I needed to turn. Works like Caps Lock and Shift.