Quite a lot of people have been bugging me about it, and finally got some time, and worked on it.
Long story short – it works.
You can add your query below plan (in separate text area), and then it will be displayed as one of tabs
For example, check this plan.
It also works sensibly-ish, if you want to obfuscate your plans, as you can see here.
In case you're interested in technical details …