Question: When someone puts on a talit to lead services, should he recite a berachah?
Answer: To rephrase this question: Does wearing a talit for the sole purpose of giving kavod to a congregation necessitate a berachah?
The issue is not clear cut. The Ba’er Heitev(Orach Chayim 19:4) rules that a talit worn only for purposes of kavod does not require a berachah. The Pri Megadim (Orach Chayim, Aishel Avraham 14:6) states that donning a talit for an aliya mandates a berachah.
The Aruch HaShulchan (Orach Chayim 14:10) distinguishes between two types of kavod requiring the donning of a talit. Donning a talit for prayer (e.g., chazzan or Birkat Kohanim) necessitates a berachah,but donning a talit for other temporary purposes (e.g., sandek, mohel, aliya to the Torah) does not necessitate a berachah.
The Mishna Berurah (Orach Chayim 14:11) suggests that the chazzan wear someone else’s talit while specifically having in mind not to acquire even temporary ownership of it.This removes all certainty since one does not make a berachah on someone else’s talit.
This solution seems to be the most pragmatic. Accordingly, my minhag as a rabbi was to direct the chazzan to use a borrowed talit and to have no kavanah to acquire temporary ownership. (After I delivered a shiur on this issue, one congregant purchased a talit for this specific purpose.)