Hi Stefan, yes, they make Burke's resemblance to Jeremiah part of the pattern of Barnabas' jealousy of the Burke/Victoria relationship in the later part of the 1967 storyline.
When Burke and Vicki announce their engagement, Barnabas angrily exclaims "Jeremiah!" I think Burke overhears him and the oddity of the exclamation fuels his investigation of Barnabas' background.
This isn't really relevant to the topic, but I personally find Robert Gerringer (vintage '67, obviously) much cuddlier than Anthony George. Each to his own, I guess.
G.