Questionable Procedure:
This suggested procedure of lowering the gear in severe turbulence just has to be dreamed up nonsense. I flew DC3s for 11 years with two reputable airlines and there was nothing in their operating manuals about this. Why should there be ? Increasing the pendulum affect in turbulence is the last thing any pilot would want.
Also I just happen to have a reprint of the DC3/C47 flight manual issued by the USAF dated 15 March 1963. On page 9-4 of the section dealing with " Flight in Turbulence and Thunderstorms " there is the enlarged word " CAUTION " and following on from this is " Do not lower the flaps or gear since structural damage may occur " Doubt if there is anything more definitive than that.
James.