Well I teach the tried and true way. 2 squares 7/8ths inch larger and sew down each side of the middle. I also use the 4X4 flying geese ruler method. But when I need many HST's I use my Wonder Cut Ruler. I also have learned to be really gentle on the pressing of the HST's as that is where they will go wonkey. So sorry you have had a bad experience with that method. The new Fons and Porter ruler Block Loc may save you. Check them out. Happy Quilting!
Luann