Yes It can be. I really want you to read "confident ruby" @s01us. I was ranting about it, so was Rich. The relevance of every single page to our everyday work is frankly almost scary - If you don't read this book really soon, I'll be disappointed and feel like we're missing out of a code skill upgrade.

Anyway section 4.2 "Call back instead of returning" covers this pattern. The advantages are explained really well there. 

I've shared the book via hipchat, it should still be available via the attachments log.