Hi - I'm the PP that recommended the vinegar. Yes, I find that the vinegar taste / smell does dissipate after they are cooled. An eighth of a teaspoon might be less than I put in. Instead of dash, I should have written "splash." It's probably more like a teaspoon or a teaspoon and a half.
I found the key to making the vinegar trick work is to put the eggs in cold water, add the vinegar, do not add salt (my mother always used to add salt to egg boiling water but I feel like the salt affects the vinegar because they weren't easily peeled when I added salt), heat it up to a rapid boil for 5-10 minutes, let stand for 5-10 minutes, run under cool water and put in the fridge.