All of this is accurate. The 1.6 will add more lift and some duration to the valves. They also add more force between the lobe and lifter which is multiplied by the spring rate. I never had a problem with longer rockers on stock cams besides pushrod hole size, but on max effort motors... It's a good way to crush the lobes to dust. I do agree with them being a bandaid for wrong cam choice and I really don't like the extra effort in measuring pushrods involved in them. I wouldn't recommend a longer rocker unless the motor was already well broken in and you wanted to see what a little extra valve opening would do.