I did find this on the IRS site:

There is a de minimis rule for a single trade or business that has income from both specified service activities and other activities. The de minimis rule states that if a trade or business has gross receipts of $25 million or less and less than 10% of its gross receipts are attributable to specified service activities, or gross receipts of more than $25 million and less than 5% of its gross receipts are attributable to specified service activities, the trade or business as a whole is not an SSTB. If, however, the gross receipts from specified service activities exceed the percentage specified in the de minimis rule, the entire trade or business is treated as an SSTB.

So if their total receipts are 2 million and receipts from consulting are $100,000 then I take it all income is not SSTB. Does that sound right?