I have never heard of this before. If this were true then cloud ceilings would probably have to be at least 2500' AGL at all radar airports, and visual approaches would be unauthorized at most non-radar airports. AIM 5-4-23 spells out visual approach requirements very specifically:

5-4-23. Visual Approach

a. A visual approach is conducted on an IFR flight plan and authorizes a pilot to proceed visually and clear of clouds to the airport. The pilot must have either the airport or the preceding identified aircraft in sight. This approach must be authorized and controlled by the appropriate air traffic control facility. Reported weather at the airport must have a ceiling at or above 1,000 feet and visibility 3 miles or greater. ATC may authorize this type approach when it will be operationally beneficial. Visual approaches are an IFR procedure conducted under IFR in visual meteorological conditions. Cloud clearance requirements of 14 CFR Section 91.155 are not applicable, unless required by operation specifications.


Unless there is something in the ATC handbook that I am unaware of, I don't see any mention of an MVA cloud clearance minimum.