One particular Weberian concept that I strongly disagree with is the notion of "de-classing." This is evident in the standard Marxist definition of the "intelligentsia" as some abstract social stratum apart from class which, by the way, was first made by none other than Kautsky himself.
"A new centrist project does not have to repeat these mistakes. Nobody in this topic is advocating a carbon copy of the Second International (which again was only partly centrist)." (Tjis, class-struggle anarchist)
"A centrist strategy is based on patience, and building a movement or party or party-movement through deploying various instruments, which I think should include: workplace organising, housing struggles [...] and social services [...] and a range of other activities such as sports and culture. These are recruitment and retention tools that allow for a platform for political education." (Tim Cornelis, left-communist)