MathML suggestion: set-theoretic symmetric difference content operator

Robert Miner wrote:

> The working group has set itself the task of getting out
> a draft  by the time we next meeting in early November.  This next
> revision (version 2.0) will be the last one for a while, since the
> W3C Math group's charter runs out in February. 

Sounds like a last call for suggestions is coming up.
Can I press my luck?
How about a symmetric difference set theoretic binary operator,
in addition to set difference?
(A symmetric-diff B) = ((A-B) u (B-A))

Hugh J. Devlin