Even if you are not into special rulers, The
Bloc- Loc HST ruler is amazing and worth having in your collection of useful tools. I was pretty good at making HSTs before I got this ruler and now my HSTs are perfect even if I do say so myself. This one ruler made a significant difference in my piecing.
Here is a sample of the results when using the Bloc Loc HST Ruler:
http://www.quiltingboard.com/picture...w-t230816.html
As far as HSTs being oversized and trimming them down, it is the usual method so that they are the correct size. When working with bias edges some distortion may stretch the fabric so making them a little bgger and trimming to size helps with accuracy.
peace
EDIT: There are lots of needs when it comes to making HSTs. If you need a lot of one kind of HST in the same color the strip method or triangulations is a great way to get alot of the same HST.
If you like scrappy quilts and are making alot of different ( fabric) HSTs then one of the other methods works great. Use the method that suits the project. I make a lot of single HSTS for scrappy quilts so the Bloc Loc works great for me.
Also, I double starch my fabrics so they are almost like stiff paper. It helps to control the bias edge.
peace