Joined: Jan 2010
Posts: 9,809
Likes: 1,784
From: Northern California
Bikes: Cheltenham-Pedersen racer, Boulder F/S Paris-Roubaix, Varsity racer, '52 Christophe, '62 Continental, '92 Merckx, '75 Limongi, '76 Presto, '72 Gitane SC, '71 Schwinn SS, etc.
Of course the Grease Guard ports weren't like Zerks, they would be hard to see and could even be mistaken for a rivet of the type that some of these parts featured, if not hidden altogether.
And such a grease port is very lightweight, almost like the ones in Campagnolo hub bearing covers.