White tea is a crazy, crazy mistress.
That being said, I've had some nice success using a method where I start off with a short time and then increase it with each subsequent infusion I make with the leaves. For instance, I start with a 2 minute steep, then with my next cup I steep for 5 minutes...then 7, 9, etc. From what I can tell, this system works well with every type of white I've tried. I've got some more detailed notes for Adagio's offerings here
I sort of get why different sources would give different amounts of dry leaf (1 tsp, 2 tsp, etc). With the exception of silver needle, most of the whites are loose-packers...that is, you can fit a lot less of it into one container. I think two tablespoons of my white peony weighs about the same as 1 teaspoon of my keemun black. (About 2.5 grams for each.) It's touch and go, though. Sometimes I get a lot with a tablespoon of white, sometimes I don't. To ensure consistency, I'd highly recommend weighing whites.