Honda mower blades are thin and light. This is by no means a bad thing as the design allows for a fine cut and less load on the engine.
Big and heavy is not the Honda way. In my opinion, Honda has always focused on performance and efficiency. So, I can not criticize Honda blades. Instead I am quick to say I am sure Honda knows what they are doing.
As far as sharpening Honda blades goes, I never sharpen them with anything but hand tools. Electric grinders and even improper use of a wet washed power stone can overheat Honda blades.