Capn Bloggs:
VMC flight at low level can be safely accomplished within a 4.2nm circling area so you do retain MDA protection; not sure about in a TERPS area...
See Post #37 for TERPs. Perhaps in 10-15 years the new TERPS CTL protected airspace will migrate throughout all TERPS IAPs.
In the meantime, 1.7 miles for CAT C and 2.3 miles for CAT D is absurd.