Sometimes we want <ul> inside <p> [1]. It works in DOM, it works in XHTML. And before "you should not want to do it" argument GML (SGML predecessor) had paragraph without indentation so text can continue after list [2].
> The pc tag identifies a paragraph continuation -- that is, one or more sentences related by their subject matter to a paragraph which has been interrupted by an address, example, figure, list, or long quotation.
> Usage: The paragraph continuation can occur after the sequence consisting of a paragraph unit followed by an address, example, figure, list, or long quotation.
:p.The subject of a paragraph might be continued through
:sl
:li.an address, a list,
:li.an example or figure, or
:li.a long quotation, :esl
:pc.and continue to be discussed in flowing text.
The discussion could continue indefinitely through
To long to quote entirely [3], unfortunately IBM destroyed online version
> The pc tag identifies a paragraph continuation -- that is, one or more sentences related by their subject matter to a paragraph which has been interrupted by an address, example, figure, list, or long quotation. > Usage: The paragraph continuation can occur after the sequence consisting of a paragraph unit followed by an address, example, figure, list, or long quotation.
To long to quote entirely [3], unfortunately IBM destroyed online version[1] https://www.google.com/search?q=list+inside+paragraph+site%3...
[2] SH20-9160-0 DCF Generalized Markup Language GML Users Guide, First Edition (July 1978)
[3] http://sergeykish.com/gml-element-pc