<p>Ok, so now we clearly see that you really want to supplement the tag system with a bunch of meta-tags describing what kind of answer does the OP want.</p>

<p>This is:</p>

<ul>
<li>Against official SE policy clearly formulated on blog. (I should stop now)</li>
<li>Redundant. It's like ordering books by cover colour -- it may look organised, but has no real value.</li>
<li>Complex. This is a whole, non-obvious system that must by manually managed. No new user would get an idea to follow it; also it has no homologue on other SEs, so it would be confusing for SE-aware new users too.</li>
<li>Revolutionary. Implementing it would require to manually (!) retag all the old questions, leading to a total chaos.</li>
<li>Short-circuiting. It gives user an option to tag the question with meta tag only, so effectively giving no topic tag. This leads either to the destruction of real tag system or necessity to make manual tagging. </li>
<li>It would make a properly used [numerics] a meta-tag. </li>
</ul>
