The difference between $({ { } },0) and $({ },0) isn't the number of bracket sets.. its the format. The first will fail because of mirc internal handling of '<space>?<space>' for certain brackets. Another way to avoid mircs internal handling of these, for now at least, is to use control charactors in front of them
Two ctrl+r's should do the trick, without affecting any other text formatting that is on or applied to the string. (dont need the $() then either)
It would be nice to see a better way to do this though, something similar in nature to the ! prefix, but to preserve all non vars/binvars/identifiers 'as is'.