Well after actually looking at that picture,,it just looks to me like they wasn't much grass,[very tall],cause I don't see a windrow,,,and if your fronts digging in,you need to raise the front with three point so it don't,,my kk brush hog works very good on grass,,don't cut mine till its 4 ft tall sometimes in spring,have never sharpened the baldes in going on 5 years of use,,using a chain instead of toplink will help keep rear wheel,in your case wheels,on the ground,for a more even cut,,,but looks like it did alright,,just raise the front end up,,,get the deck about level,maybe 5-6 inches off ground,,set your tail wheels as close as they can be set to 5-6 inches with deck about level,than do the rest with three point,,you ain't going to get it exact,,like I said a couple of times a chain works better than a top link,,,I use from 1/2 to about 3/4 throttle,I'm sure half is less than recommened speed,but it still cuts good even at 1/2 in light short grass,,I don't use more than 3/4 for 4 ft thick stuff,,I don't go fast but I don't creep,,maybe a fast walk generally,slower in thick stuff generally,,,thingy