I think the problem is that Italian dressing in the true sense, that is, as italians eat it, is not done as an emulsion or mixed together in bowl or bottle, but is made directly on the lettuce in the big common salad bowl you serve it from. It's not a question of being a "purist". Who cares about authentic, as long as it tastes good. But it seems many of you are agreeing that your "italian dressing" is just not that good. Maybe because that's not how it's supposed to taste.
An old Italian saying for dressing salad goes: be a spendthrift with the oil, a miser with the vinegar, and toss, toss, toss. The tossing is essential. It's like pasta sauce, it';s not poured on the center of the pasta but is mixed already before bringing the big bowl to the table.
Also, since it;ls so simple it relies (like most italian food) on the quality of the raw materials. Good extra virgin olive oil. Good vinegar (i only encountered balsamic here some ten years ago, before it was always wine vinegar, though i do prefer balsamic).
If you want to make an italian salad dressing, you really have to coat every leaf, tossing and tossing the salad, and you pour your oil and vinegar (sometimes some people use lemon instead) and salt (some, like me, can't eat without pepper) directly on the leaves. That's it. No herbs. You're supposed to taste the lettuce and carrots and tomatoes and whatever else is in season (fennel, celery, other greens like arucola).
Not to say you can;t do what you like with oil and vinegar, but what you';re making is a vinaigrette, it;s french and it;s not really italian dressing. Also Italians cut up their lettuce, (horrors!) into bite-sized pieces. This facilitates the oil getting everywhere. If you cut your lettuce with a sharp knife it won;t bruise or anything. I don;t see why not. I think tearing it makes the likelihood of bruising it (with your hands) much greater.
Putting a bunch of herbs in means you taste only herbs, not the salad. So if you want herbs, probably you should choose one (chive? basil? origano?) and use it fresh so it;s not so pungent.
1:4 vinegar to oil is way too much. You don;t want something sharp, you want somethinhg refreshing. In fact it;s eaten after the main course. Pasta or soup, then meat and veg, then salad. Cleans the palate, makes you feel good. So a little acid (vinegar or lemon) and crunchy salad and oil, preparing the way for desert or cheese.
I do it always by eye - i put enough oil to make the lettuce glisten when i toss it, and then vinegar measured in drops not in cups, not even in tablespoons. I salt it and pepper it from the shaker like i would salt something in my dish, imagining the various layers of salad as if it were a series of servings one on top of the other. Everybody seems to like my salad, on both sides of the ocean.
Oh, and i do do something that is highly irregular here (definitely not a purist) and i rub the salad bowl with a cut piece of garlic. It gives a very subtle taste that nobody can detect but is very pleasant.
