This may have been true as recently as the early 1960's,but it's not true anymore. Win Silvertip 200gr JCP's are supposed to run somewhere around 900fps out of a 4 inch barrell,so a 3 inch barrel isn't that much of a handicap. I'm going to have to dig out my chronograph one day and clock them out of my Rossi. I know they expand like a champ out of my Rossi. The high-pressure version of the 44 Special is called the 44 Magnum.
In either case you, hand-wrist-ears, will definately know when it goes off in a short barreled light gun.
Whoever told you this has never shot one. The average 10 year old girl could shoot one with no discomfort.