There are so many things like this that are challenges we just have to suck up.
Like, how do you write a multi-stage message where multiple stages are absolutely unavoidable, without the recipient answering just the first bit and not reading the rest?
I really struggle with it. (Because I am verbose. Overly verbose.)
But I try to frame that request in the context of each message.
Whereas someone I know has basically a copied and pasted demand letter at the top of each email, saying he won't reply unless people have read the whole thing. It's not as cute as the legendary Van Halen rider M&Ms request [0], and it just comes across as damaging.
[0]: http://www.thesmokinggun.com/documents/crime/van-halens-lege...