I ran into a situation at worlds where I wanted to measure distance and the opponent said, "you're not allowed to measure here." I think it was trying to determine if a person was inside missile range prior to picking an action.
So, I thought I'd put it out there. When can I and when can I not measure. I know I can measure a barrel roll prior to doing it to make sure it's possible. I also know I can't measure prior to setting my dial (obviously). Other than that, help a dude out.
Sunny