Before I grew up and got a real job, I was an attorney (I guess that makes me a recovering attorney these days -- kind of like an alcoholic in that you can never quite live it down). Anyway, I couldn't help but chuckle about the requirement that motions of discovery be "reasonable" because I saw a lot of very unreasonable requests filed.
If a plaintiff is suing a corporation with almost unlimited amounts of money at hand, it's a common practice for the defense lawyers to file motions asking for ridiculous amounts of documents as a way to harass and bully the opposition. It's a sleazy tactic which, sadly, is very effective.
Some reform in this area is desperately needed.