I disagree with the proposition that a DE blade going agains the grain will have “play” just because you have a thick beard. In my opinion, whether a DE blade has play or not solely depends on the razor used. Some razors lock the blade in much better than others.
With respect to the difference between DE blades and SE Artist Club blades, there is no doubt that the SE blades are thicker and stiffer. There is also great variety amongst SE blades, with some being much sharper than others.
As to whether you will have less, or no, irritation with an SE blade, you will only know if you try them. Again, from my experience, shaves with SE Artist Club blades usually provide me with the closest shave to a straight razor and with no irritation. But, I have had equally good shaves with DE blades. Many times, it depends on so many other factors in the shave, like beard preparation and proper lathering.
The above being said, try shaving with a Blackbird Asylum and a Schick Proline blade. That should provide an excellent comparison for you.