I kinda doubt both of those statements. I mean maybe I could believe in the first one if your filter is creating a huge raucous, but more than likely it would be fine. I have an anubias attached to a root and the top leaves are constantly in motion from the filter outlet, but it also looks like the healthiest plant in my tank, presumably because of the good flow of nutrients through that area. Also, unless youre heating a discus tank or something, having a heater periodically turn on to maintain 74 degrees isn't going to burn your plants up. Most all planted tanks with tall background plants have plants that are hiding heaters and they look no worse for wear. If you run into a situation where they are, move your heater a few centimeters this way or that way and problem solved.