Binding keys....

Is it legal in TWL to bind "Fragout!!" to key (with no action binded with it) ?

yes....commo binds are ok

Yes, and you could also bind the commo message to an action like Yell Fragout when you toss a smoke nade

Thanks for the info

so what about zoom in + mouse sensitivity change? is that a double action?

Im pretty sure its legal, but you would have to be careful on how you did.

From the rules: Binding Gamma, contrast, and brightness changes to keys is legal, as is changing mouse sensitivity. If your mouse change reduces the recoil of what the gun would normally do, that would be illegal. An action is anything that the soldier would have to physically do.

And since it is not an action it should be legal to bind along with your zoom. But I am not 100% sure about this one.