1. Potassium isotopes are not accurate in rock less than 100,000 years old due to the relatively long half life.
2. Sampling protocol includes measurement of background argon levels.
3. Steve Austen is notorious for misstating sampling protocol and has tried C14 dating on coal millions of years old while knowing that the limit on C14 dating is 50,000 years at the outside.
4. Layering of volcanic ash is a special case and in no way similar to limestones, mudstones, sandstones, salt(which has the tendency to rise above the layer of its initial deposition), granite, metamorphic rock in total, etc.
Limestone, in particular, which forms in shallow tropical seas, can be found today in locations such as the tops of the Himalayas. Obviously a LOT of time had to have passed for once soft sea sediments to have first turned to stone then be raised thousands of feet.
I am familiar, but in no way as knowledgeable.
The seeming dichotomy in ‘science practices’ & discussion was my point.