Always have sharpened the tips on my danforths as well...made them OK...up from barely acceptable when working on bottoms with hard sand, shells, mussels, grass or seaweed. In those bottoms, they rarely caught easily in my experience on all of my boats and assistance towing boats I've run.
Had a friend I told about my distrust in the lightness of the fortress, even with chain....one day his 26 hydrosports went dead and he drug over 1/2 mile and through a bridge at over 2 knots before it caught...he got rid of it the next day as his primary.
I don't think fortress/danforths are bad...just tough to set...once set are tigers. That's why I sharpen the tips to the point where I think if the manufacturers did it that sharp....there would be way to much gel damage and blood.