I have read one article that one guy was practising chess on the computer. He went for a tournament and he felt disorientation while playing with a physical board during the competition.
It is definitely true that computer chess does not imitate OTB chess in the way your brain sees the board. I play 95% computer, and OTB is more difficult for me, and I miss more stuff OTB.
That's why I keep a few physical boards around I try to play with whenever I can. Inexpensive sets, really. Your typical game-board quality.
I don't think it helps reduce eye strain, but it does help with motor skills and visualization