>>5758
>>Submissiveness is already shown by which goes before the slash and which after. So g/M would be a preteen girl dominating an adult man.

While your idea looks good in theory, it is unusual and will cause misunderstandings, usually capital letters mean domination regardless of their position just like 47 explained
except that he forgot b and g letter for boy and girl what is probably the most important issue.

If tagging was done your way, I guess there should be no slash if there is no domination.
As MF is male and female on equal terms, or Mb/g male and boy dominating girl.