To test this I built a toon who started with only Tahoe patterns..
At 31 I maxed all 13 items,
at 35 I learned Edgewood,
at 36 I learned a second edge through crafting
didnt learn a single other edgewood up to lvl 70
at level 70 I read pattern CastleRock
at 71 I craft learned another one...
nearing 99 and have yet to craft learn another.
Im thinking something is turning off the insperation learning once you learn 1 from crafting.
for extra info, yes I've build up enough supplies where I can craft only CastleRock for several skill gains, so it's not "Your not crafting the Pat Group"
After craft learning CastleRock Vest, have crafted 420 straps and 210 kneepads...not one gain.