In the Question Praying Without Shoes you wrote not to prayer without shoes. What about Cohanim. They Duchan also without shoes?
The Gemara and Shulchan Aruch 128:5 that Cohanim do not wear shoes when Duchaning, because all the shul can see them and if their shoelace might tear and ludicrate them Chazal said they should Duchan without shoes. It also might cause the Cohen not to Duchan again. Rabbi Ro'i Margalit