Additionally touting the slim block submission as some technical advantage when all it leads to is every single miner starting to mine empty unverified blocks on every block change is a significant step backwards.
If you are going to (try to) rebut the article, how about you actually rebut what it contains? There are exactly zero mentions of 'slim block submission' in the article. Do try to keep up - I don't think you have any idea what Xthin is.
Apologies for not being explicit then: The combination of "Xthin" "Expedited Relay" and "Optimistic mining" that BU explicitly is pushing since you want to be pedantic about terminology, and he links the articles that describe it himself, so I'm rebutting not only what's in the article, but his own linked articles within it.
Except that 'slim block submission' (I assume you mean Xthin?) absolutely does not lead to 'every single miner starting to mine empty unverified blocks'. The two are completely orthogonal.
Xthin and Expedited Relay are both benefits to he network as a whole. Optimistic Mining is a benefit to each miner that existing incentives ensure will be implemented by miners whether they run some BU derivation, some Core derivation, or any other.
Interestingly, Xthin reduces the percentage of block interval over which Optimistic Mining is beneficial. Thereby working exacly opposite to your claim.
So what are you complaining about, again? You've certainly not articulated anything probative.