This is a summary of what I have already submitted for Public Review Issue 205 (http://www.unicode.org/review/pri205/). I am mentioning it here in case there is something wrong with my idea.
My basic idea is that one does not a 'level direction mark'. The desired effect can be achieved by embedding neutrals in a sequence LRM...RLM or RLM...LRM. They will then take on the directionality of the embedding by Bidi Rule N2. For an example, see my submission. It may be helpful to view the source of the full page view, for that has examples in HTML written solely in ASCII. Richard.
