The only reason I noticed it is that I saw the trick used before when someone photographed Mitre Peak in New Zealand. Theirs looked something like this:
When I visited the same spot, I was trying to take the same picture, but even with the water fairly still first thing in the morning, it was all choppy. Mine looked more like this:
It wasn't until later that I noticed they had used a puddle. Taking a Mitre Peak shot reflected in that puddle is a popular trick with the pros.