Disc mower opinions...

I am cutting thick, not real tall, fertilized grass hay. I have done this with a NH 617 and a Kuhn (number forgotten) without the slightest trouble. I am now running a Kubota/vicon 2028 and can’t get through the stuff. It leaves a layed over, ragged cut even with newer blades, and is leaving a lot of hay in the field-6” and longer stalks.
How do 3 blades not get this done? I have adjusted, tilted, cursed...it’s running on a caddy but I can’t see that being a difference.
Am I doing something wrong or do I need to go back to Kuhn.

Disc mower opinions...