When somebody asks you a question, you can look it up in the info manual, go back to the channel, and type /INFO. This will insert a convenient elisp command that the other person can evaluate in ERC to go to the correct node.

    (defun erc-cmd-INFO (&rest ignore)
      "Send current info node."
      (unless (get-buffer "*info*")
	(error "No *info* buffer"))
      (let (output)
	(with-current-buffer "*info*"
	  (let* ((file (file-name-nondirectory Info-current-file))
		 (node Info-current-node))
	    (setq output (format "(info \"(%s)%s\") <-- hit C-x C-e to evaluate"
				 file node))))
	(erc-send-message output)))