It's definitely just ActiveRecord and not ORM that cause the problem in my opinion.I've started work on an alternative which focuses on automating just the most tedious parts of writing sql then getting out of the way (and requires no boilerplate classes - it intuits the relationships from the key names). Oh and it's fast as hell and uses very little memory.

I call it PluSQL: the ORM for SQL lovers:

http://github.com/iaindooley/PluSQL/