Is It a Good Idea to Do the Schematic Design Phase?

When you're into that construction detailing phase, a lot of the heavy design work is done. And then i can pass on this information to my cad drafters and let them run with it as far as technical documents go. With a constructiond detailing phase, you end up with these really specific pages of instructions and schematic spects for people to execute. I think those are the type of clients that would be very hard to do a value based fee on.