I read about this kind of thing in the '70's. A psychologist named Rollo May, if I recall correctly, decried such things in general as an attempt to go through the motions without feeling much sensation. If the idea is to desensitize the penis in order to have longer stroking time before ejaculation, that was what he was talking about.
This may not be on target for your question, but it's all I know. Hope it helps.