The problem with the jigger is it has the stigma of being "cheap" as opposed
to free pour, where customers think they're getting more alcohol than they're
supposed to. Most people (at least in the US) would rather have more alcohol
than a perfectly balanced cocktail. Anyway, how many good chefs do you see
using measuring tools for salt, spice, etc.?
And I count both ways. The most important thing is internal tempo. If your
tempo is off, it doesn't matter what numbers you say... you're not pouring
accurately.