Super advice. I have been working with Coco for a year now. He came to us at 16 months old with zero recall, he now has excellent recall (without distractions!)..but it's always "work-in-progress". I love training with him, he shows such a joy for learning.
I have the arms wide as a recall signal, too. It evolved from when they were puppies, encouraging them in. They respond really well to it - but doesn't work if they're facing the other way or got their nose in a good smell