I would say that you would mostly find microgreens as a salad addition or a garnish or a flavor enhancer and not as a salad by itself. There are exceptions.
Depending on tray size, let's say your standard 10x20, I sow at a rate of 24-40 grams per tray of a Basic Salad Mix. I also grow their Spicy Salad Mix and Rambo Radish but currently, that is only for home use.
Yes, you can cut with scissors or a very sharp produce knife. I use both. If you are not harvesting an entire tray at once, you need to make sure your cutting utensil is sanitized between cuttings so that you don't introduce mold or bacteria. At the restaurant, I cut a quantity needed as I get each order. It was literally a living plant at the time you place your order. It doesn't get much fresher than that.
If you want to grow salads, we did "cut-and-come-again" salad boxes when I was working the Jr. Master Gardener program at the local public school. They were similar to the one in the link though ours didn't have a stand and I took them home between weekly meetings to care for them.
Super Salmon Bagel: Cold-Smoked Salmon, Local Organic Hard-Boiled Duck Egg, Local Microgreen Mix, Heirloom Tomato, Shaved Red Onion, Capers, Dill Cream Cheese on an Organic Everything Bagel
Railway Bagel: Heirloom Tomato, Cucumber, Carrots and Microgreens with Hummus on an Organic Super Sprout Bagel
