Apart from the overshot card cartridges issue, which I don't remember reading about
(memory falters), Garwood was a great advocate for the mentioned combination (cyl/full).

His reasoning was that most first shots were taken at around 25 yds and at that
distance cylinder choke worked very well. The shotcup choke reducing factor has to be
considered in this day and age. JMTC.

JC

"...it is always advisable to perceive clearly our ignorance."ť Charles Darwin