(Quote "but if you centered the front, it was quite effective").
This is the great misconception about appature sights , after all these years...There is no "centering" needed, the human eye will automaticaly seek the most intense spot of light, which in this case is the center of hole in sight. All one needs to do (assuming the rifle is sighted in) is put the front sight where he wants the bullet to land.
That said, I too am a great fan of appature sights. Mike venturino wrote that a good vernier tang sight is like a 1X scope. It's kind of funny, I have an Axtel sharps chambered in .40-70 21/2". With cast bullets, I can hold groups in an inch at 100yd...Not always, but more times than not. Once in awhile, some hot-shot will come to range with latest whiz-bang boomer equiped with a scope more at home looking at solar system. He'll start to brag about his 2" groups, then turn to me and ask if I even hit paper with that smoke pole. His smirk fades when we go down range. What a hoot!