One thing that springs to mind about the week he spent with us was that he was suddenly spooked by the chlorine floater in the pool!
I am sure we've had one before, but this time Volt didn't like it at all. He was barking at it and giving it a wide berth when he walked past it in the pool (if it was close to the edge).
This would not do, of course, guide-dogs can't be spooked by anything and a big part of our puppy walking work is exposing the pups to every possible kind of scenario or noise they may encounter in their every day life.
I took the floater out of the pool, stood it upright on the bricks and sat next to it, quietly praising Volt if he came up to it without flinching. Eventually his curiosity got the better of him and he sniffed it with his neck at full stretch. I put it back in the pool and Volt responded as he had before, but with gentle encouragement and praise for ignoring it, he got over it and within a couple of days he was bopping it with his nose when it floated by him (he loves lying on the side of the pool with his nose under the water).
I was also able to see a difference in Volt's behaviour on-lead since he started his training! Its very impressive to have him not pulling at all!