I believe that is true of contests but not of conflicts. Its not spelled out 100% in the rule book but I have read on the forum that you can not create a conflict pool with more then ten dice to net automatic bonus nudges.
Sorry for the delay, Cen.
On page 138, 'Each roll is made with 2 to 10 dice, otherwise known as your "pool."'
On page 142, 'The largest any
pool can ever be is 10 dice. If your pool ever
grows above 10 dice, it remains at 10 dice and you gain 1 "free" Nudge for each die beyond 10."
The bold is mine. I don't see any differentiation being made between pool types (contest vs. conflict) in the rules. I believe the forum thread you mention concludes with a rule change for Feruchemists tapping Pewterminds, but I believe that the ruling was an exception specific to that situation and not a general rule.
Hope this helps!