Love 'em or loathe 'em, Half Square Triangles are everywhere. There are tons of ways to make them, and everybody has an opinion on the best way to do so. Some people make their squares 7/8" bigger than the finished HST needs to be and do not trim. I'm a trimmer, though. It is a pain in the behind, but I've never had a problem with my HSTs not matching up even if they were used in a design with squares or something besides other HSTs. Did you know that by using the "non trimming" method you are actually creating HSTs that are 1/32" off from your desired size? Yup, the reason we use the +7/8" rule is not because it is mathematically perfect, but because it is the closest notch on the quilting ruler. That might not be a big deal if you are making a quilt of ALL half square triangles, but if you are incorporating them into a larger design, that mistake can add up quickly, especially on a very large quilt.