I'd say there's a 99% chance that ADL will be faster than Zen 3 in most use cases, especially single threaded or at equal core counts. Of course, by then, Zen 3 will be a well established product line and AMD can make Intel's life pretty hard and the success bittersweet with adjusting the prices properly. Then the ball will be in their court, to bring Zen 4 out in time.
Single threaded ADL vs Zen 3 comparisons will be measurable as we are used to and well-versed with single core-to-core comparisons.
As I eluded to in my post, multi-core comparisons of ADL to Zen 3 are going to be really interesting and I think problematic. At least at first until we get a handle on how to make these comparisons. What will our performance comparison metrics look like?
8 core Zen 3 vs 8/4 ADL?
Or 12 core Zen 3 vs 8/8 ADL?
What's a little core worth in terms of a big core? How do the big and little cores scale/work in various multithreaded apps?
I think with the CPU market starting to differentiate architecturally now more than ever, clock speed and cores are starting to matter less and less. The end result is simply how does this processor compare with this one, which has been how the non-tech geeks (not us) have been looking at this from the beginning.
For people like us who think about these things during idle moments it's going to be super interesting when this clash get going in earnest. The really fun part will start once RKL hits the ground and we get real benchmark data and analysis from Ian. I'm also thinking Intel may creak open the door just a bit on ADL soon after RKL just to keep our attention on their side of the table.
On the other hand, AMD is sitting pretty thinking, "What me worry?" I've got the fastest architecture, the most efficient process, and I'm selling every single chip I can produce.