I'd point out that the Storm Tactics book really isn't designed for modern sailboats...it wasn't really written with high-aspect bulb keel boats in mind. It also wasn't written with multihulls in mind. While the book, updated last in 2008 for the 3rd edition, is a great resource...saying it is for modern sailboats is not quite right.
??? It specifically addresses the issues of heaving to multihulls and high-aspect bulb keel boats, including specific case studies, testimonials, and techniques for these boats.
While the Pardeys themselves have a more traditional boat, they do yacht deliveries and test these techniques on modern boats.
I can't say from personal experience that a modern boat wouldn't create a slick, but it seems to me that any boat (even a powerboat) would be able to create and remain under a slick if lying at a hove-to angle under a parachute sea anchor.
Also- we're talking here about the C22, not an Open 40.