If you want a more robust string, try using a #8 guitar string instead. Just make sure it is straight and doesn’t destroy any plastic parts from being bent up or down too far.
Well I’ve been doing it that way for years and my St. Augustine looks better than ever. My empirical evidence would disagree with you. I’m no scientist but I know plants need nitrogen(from grass clippings) and carbon(from leaves) to be healthy.
You have to rake up the leaves but then you can load in armfuls at a time. The hopper probably holds at least a bushel at a time and is continuously emptying itself and making more room while it’s in operation.