I agree! If you try to go to each task and add or remove assignments. Instead, on the Project Resource Page, you have the option to move many or all tasks at once.
While on the Project Resources page, look for the resource who WILL RECEIVE the task. Project Insight focuses on who will take the work - not just "get rid of someone's work." Look for the clipboard icon in the desired resource's row:
Slice of PI explains Placeholder Resources. If you fast forward to minute 3:29, you can learn about the mass assign feature.
You can also watch the entire episode. I think it's hilarious. I think I'm very funny.
I'm more interested in hearing what you think. Funny? Helpful? Could use some work? What do you think? Put it in the comments below.