Walker was "absolutely rapt" by the 23-year-old Bay of Plenty paddler's progress in the 500m in the space of a week, from winning the B final in Hungary to topping the podium in Racice last weekend.
"What's impressive about her is her ability to learn.
"Mental toughness is often a phrase that's biffed around but not really understood. She's tough in the right areas, and often that's about being disciplined with your thoughts, not allowing yourself to be negative."
Walker wasn't surprised she won the 500m, which she's contesting seriously for the first time.
"That's the kind of stuff I've seen her do in training, but it's another thing to do it in this environment.
"No one ever won a race with their training diary. In the 500m she destroyed the field. That wasn't luck."
However, despite compelling early evidence that having a serious crack at a 200-500m double at the Rio Olympics in 2016 is a realistic prospect, Walker is cautious.
"It's such a long way off. Absolutely before the project started she had that belief and this [the Racice double] probably only helped confirm that."
As for Carrington, she has had a thought confirmed in her mind. This trip was a feeling out of the idea of a double dip in Rio. She needed to test the waters.
"My goal is to go to Rio in both but I don't want to count my chickens before they hatch. It's good to come here and go 'okay, I can do this'."
The third and final cup regatta before August's world championships in Duisburg, Germany, is at Poznan, Poland, next weekend.
