Is the Torah reader (baal koreh) allowed to touch the scroll with the yad or not? (Possible reasons: Allow to create a physical contact with the words of Torah; disallow to avoid premature damaging of the scroll.) Is the answer halacha or custom?
I always understood that, even if not forbidden and often seen, one should not touch the parchment with the yad to prevent erasing letters over time. I see R Hershel Schachter writes the same (Lesser Known Laws of Torah Reading, #54)
The Ba'al Keriah should not touch the Torah text with the tip of his pointer, even for the purpose of keeping the place, lest he contribute to the wear and tear, and eventual fading of the letters. For the same reason, the Oleh should not touch the actual words with his Talit before beginning his Aliyah.