Mozilla's message to certificate authorities

Don't. If employees want to take responsibility for their own devices, let them, and kick those devices off the network if they do anything wrong (e.g. spam/virus/botnet/illegal-activity/etc).

If you have a security environment with severe restrictions about compartmentalization of information, stick user-managed devices on a separate network segment without access to sensitive internal resources.

What, exactly, do you expect to gain by sniffing SSL traffic from a user's personal smartphone?