I made this as part of another CL recipe, 'Flank Steak-and-Blue Cheese Quesadilla Salad' (also from June 2001) and it worked great. I used most of it to marinate the steak but did use it as a base for the recipe dressing that did add sugar and thyme. Very good in this usage. Can't say I'd like it well enough as just a straight salad dressing - at least not without adding a bit of honey or sugar.
I definitely disagree with the first post - this is hands-down my favorite, simple, go-to dressing! I've been making it for years - I make it at least once a week and always have a jar of it in my fridge. Using fresh lemon juice and stone-ground mustard is key - the flavors play beautifully upon each other.