I don't recall what the normal procedure is, if any, but it is worth keeping in mind that Council approval is required not because TEI-C wants a gatekeeper who would keep foolish SIGs away, but rather just a) to help prevent duplicate SIGs, and b) so that someone is paying attention to what SIGs there are and who is the contact person for each.
I received an email from Dario Kampkaspar who is asking for the official approval of the SIG on Newspapers and Periodicals. The minutes from their meeting in Victoria contain the main interests of the SIG, see https://docs.google.com/document/d/1i0ow7-rfjg2OLwuyzXlk-u7P0nWLN5MP9VWUed1E.... I read through the SIG rules and wonder if the minutes are enough for a decision or if I should ask him for a summarized proposal / mission statement? I tend towards the latter. What do you think about it and what is the standard procedure?