That's a good point, and of course that's how utahjazz7 recommends doing it in his tutorial. I find things much easier to handle by making each animation a separate file. It takes up much more disk space and makes rendering more annoying but it's a lot easier to create the animations. That's especially so in this case, where different tools appear in different animations.
By the way, Rob - I just sent you an email.
By the way, Rob - I just sent you an email.