Removing the pop-up labels (application names) from the dock?

I want to get rid of the pop-up labels which appear when you mouse over dock icons. I've routed around in the dock plist, and found that I can achieve this for items that are permanently in my dock by just blanking their 'file-label' string in the dock plist, but was wondering if there is a way to do this for all items in the dock?

I've tried adding every logical 'key' to the plist file, I can think of, with a false boolean value, but to no luck. I'm pretty new to OS X.

Many thanks if anyone can help me solve this!