For sure and apparently Bailey's refinement came soon or at least within a few years.
Found this looking for Gapen's original recipe,,,.
Gapen's original Muddler had a fairly sparse and
ragged head of loosely spun deer hair, but the more
densely spun and clipped head found on today's
Muddlers was a refinement by Dan Bailey. In the late
1950s, Muddler Minnows of various types accounted
for over half of the oversized trout (4+ pounds) immortalized
on the "Wall of Fame" of Bailey's fly shop.