The obvious answer is Nynaeve using herbs as her crutch to enable her to Heal via Channelling.
(She needed herbs to Channel for Healing through book 3. She needed anger for non-Healing Channeling - such as during the lesson with the Amyrlin in book 2 - and then up until she breaks through that block in book 7.)
There's also a chapter where Moiraine uses her blue stone to focus her eavesdropping, and muses that it was the first trick she learned, and ISTR there's a mental comment about how many Aes Sedai have such little tricks, but no examples.
I think the generalized Magic-According-To-RJ rule is: Channelers often stumble into their powers in puberty, and only after they manifest are they usually taken for organized training by Aes Sedai (or Wise Ones, or Windfinders, or Sul'dam, ...) As a result, many new channelers confuse, or conflict, their inborn ability with props - they don't have the holistic understanding of what's happening to them, so it's easier to be a bottle-shaker.
It's clear with wilders, in particular, how strong this is. Nynaeve and Theodrin both blocked themselves, using totems (Herbs and healing in Nynaeve's case, and gender attraction in Theodrin's case) to clamp down control on top of the power they had no formal training in.
I think Moiraine's staff could have been sold as an example of lingering attachment to an early crutch, or retconned as an an'greal, but really it just quietly disappeared as part of the "Book One was meant to be Lords-of-the-Ring like to pull people in with familiarity, and oh look! the staff is like a wand. Nevermind, moving on..."
In response to @NaturesCreed's comment, anger was the lingering block that Nynaeve had, but herbs was the first one which she overcame. When healing Dailin in "The Dragon Reborn":
"The Wise Ones use herbs, Aes Sedai, but I had not heard that Aes
Sedai used them."
"I use what I use!" Nynaeve snapped and went back to sorting through
her powders and whispering to herself.
and then, several pages later after being robbed of her herbs,
"She is hurt badly, Egwene. I think her skull is broken, and she is
barely breathing. Egwene, she is dying as surely as Dailin was."
"Can't you do something?" Egwene tried to remember all the flows
Nynaeve had woven to Heal the Aiel woman, but she could recall no more
than every third thread. "You have to!"
"They took my herbs," Nynaeve muttered fiercely, her voice trembling.
"I can't! Not without the herbs!" Egwene was shocked to realize
Nynaeve was on the point of tears....
[Nynaeve gets angry and heals Elayne without herbs]
"Light!" she muttered. "Doing it that way... was like peeling off...
my own skin. Oh, Light!"