Why is "link text" not allowed to "contain other links"?

normal link text (special link text)continuing on with the normal link text.

<a href="#normal">normal link text (</a><a href="#special">special link text</a><a href="#normal">)continuing on with the normal link text.</a>

[normal link text(](#normal)[special link text](#special)[)continuing on with the normal link text.](#normal)

I’ve seen it be used in a few sites. but just breaking up the link should be easy enough. (And its not ambiguous, and it follows HTML spec. and it easier to implement)

I think a link should start with [ and end with ] pretty simple. all other methods would be ambiguous. (which was probably why html dissallowed it)

inline links are also not as easy for a human to read.