Phal new leaf smaller than older leaves

[Fuzzy]

Hello, I have a question. What causes new Phal leaves to be smaller than older leaves? I always thought it was a sign of stress and bad care, but here I have a Phal Surf Song that is clearly thriving. The old leaves are about 7.5-8 inches long, and it recently put out a new leaf that is only about 5.5 inches long. What's even stranger yet, immediately after this leaf stopped growing I noticed yet another new leaf starting to develop! Why would a Phal abandon growing one leaf only to start a second new one right away? One thing I changed over the last couple of weeks was I turned the phal 180 degrees as the new leaf was leaning too much towards light and I wanted to "even it out" a bit. Could this have caused the leaf to stop growing? I am attaching a picture of the phal with the smaller leaf and a pic of the roots with all these tips coming out of the pot. As you can see, lots of root growth, no rot, etc.