I agree with everyone who does not find actionable projects acceptable. It is not a question of "choice". OmniFocus is not a feature rich task manager, it's a GTD tool, frankly, it is the only one. If it ever stops being one, I will return to Ken's GTD extension for OmniOutliner.
I'm not a fancy-pants GTD purist, but if I wanted a tool to manage my upcoming tasks next week, I would not need GTD. GTD is meant to manage all aspects of your life, and if the system "works" for you, you will end up with many hundreds of items in it (the "maybe someday" projects, the deferred ones, things that I know I need to do in 3 years from now, etc.)
The glory of GTD is that even with this huge amount of projects and tasks in it, it completely avoids clutter and draws your attention to what's important here-and-now.
EXCEPT if you start to treat projects as actionable. Then clutter is unavoidable.
There is absolutely no way to organize your projects well AND make sure every single parent item is actionable. "Sell car to Mike" is NOT actionable, and will never be (try). But let's say for argument's sake that it is, how would you make sure your other 50 parent items are also actionable? Have all an appropriate context? An appropriate timing?
And I won't even get into why reviews are important, instead of just "ticking" out your projects in context mode.
Discussing how NOT to do GTD with OmniFocus is like discussing how to make an artistic drawing in Autocad. You can if you really really want to, but why on earth would you? There are simpler, cheaper tools out there for you to do that.
Anyway, you can to some extent disable this horrible, horrible function, but the trend here remains worrying.