A lot more often than it seems I should, actually. I do a lot of rapid OO prototyping, often before I want to propose a new design. As such, I don't have a design laid out and agreed upon yet. So, I'll try different things, move things around, try and figure out where things really want to live vs. where I think they should live.

How often have I used MI? Less than a handful. How often have I thought of using MI during rapid prototyping? Too often to count.

That's why I use base qw(Foo);

------
We are the carpenters and bricklayers of the Information Age.

Don't go borrowing trouble. For programmers, this means Worry only about what you need to implement.