I don't think that is unique to persimmons. I think that is one of the big challenges of starting trees in general early indoors. There are several factors. One is light. My trees grow like mad indoors, but no matter what indoor lighting you get it does not have the intensity of the sun. So, leaves that formed indoors can be very sensitive to sun scald when moved out doors. If you do it early in the year, they are less sensitive because the sun is not as intense when lower in the sky. This lets them adapt more slowly without constantly moving them.
The problem with that is the second issue which is temperature. I find if I move my trees out early (but after the last threat of frost), their growth stalls. I believe the cool nights confuse them after developing in 70 degree constant temps. It seems to take them a long time to start growing actively again. I'm not sure how much I'm really extending the growing season starting them indoors. When I get the timing and sun just right, they can show fantastic growth, but if I don't, they my be no better off than if I started them outdoors in the spring. I just don't have the time to mess with them during turkey season and spring planting time.
This issue may be different for folks in different zones from me.
Thanks,
Jack