Now that I have the confidence to re-lay the ribs, I have a different perspective on when ribs should be re-layed. It costs $400-500 to re-lay ribs most places. Add a couple hundred for re-blueing and it's not insignificant. I understand that well. However, 100 yrs of corrosion should be looked into when the opportunity arises, as when refinishing, IMO. If pinholes present themselves, I think it should be assessed as to whether these mean corrosion is prevalent under the ribs. Good, rational thought needs to go into it. I don't know all the answers, but I hope I've asked all the important questions.
Jimmy,
I don't think holes along the rib solder joint would be intentional for drainage. Pulling the front bead and flushing with a solvent may help to evaluate the condition under the ribs based on what comes out.