LessWrongers as a group are often accused of talking about rationality without putting it into practice

Evidence? Who accuses them of this? One post (on Less Wrong itself!) is not evidence enough for this claim.

who gets to be in our CEV

Since this barb is directed at me, I should respond. When I come across a superb intellect like Yudkowsky, I first shut up and read the bulk of what he has to say (in Yudkowsky's case, this is helpfully packaged in the sequences). Then I apply my modest intellect to exploring the areas of his thinking that I do not find convincing.

Note that the essay is not about "who gets to be in our CEV"; it is about whether the CEV should include all of humanity, or not. The ability to distinguish between these questions should be within the capability of a rationalist - although I expect your distortion is an intentional attempt to trivialise the subject for rhetorical effect.

Otherwise, what you have written boils down to this: “we should shut up and multiply. You people aren't shutting up and multiplying.”

Unfortunately, we are not consistent expected utility maximisers, so "shut up and multiply" can never be more than an ideal for unmodified and unextrapolated human beings. It is actually impossible to implement "shut up and mutliply" literally, if you aren't accurately described by a utility function.

Furthermore our introspective limitations, knowledge limitations and computational limitations give us no particular way of resolving conflicts between our values, even if we were expected utility maximisers. For example the value of enjoying an argument for its own sake and the value of arguing things in a strictly optimal attempt to minimise existential risk are somewhat opposed to one another. Yet even if I did have a personal utility function such that there existed an optimal way for my unmodified and unextrapolated self to resolve this conflict and maximise utility, I wouldn't know what it was!

It is sometimes fair to recommend that someone shut up and multiply, but I would only do so (I hope!) when the stakes are extreme enough that they outweigh this inconsistency. I might also do so in a specific discussion in which someone was conflicted about whether they should do something, because SUAM seems like the best possible answer if someone is going to ask what they "should" do.

But since neither of these conditions applies, there is really no basis for you saying that I or anyone else should not have arguments and discussions for enjoyment's sake alone, unless you have good reason to think that the consequences are really extreme (for example, I criticised Eliezer for not shutting up and multiplying in his proposals for CEV. Those are extreme consequences).

That said, setting aside the fact that my ability to contribute intellectually is modest, can you really see no benefit in discussing important concepts such as CEV? Why is discussion of overcoming biases worthwhile, but not discussion of important strategies for the future of humanity?

Finally, although it scarcely seems necessary to say this, you cannot expect to be taken seriously with this kind of portentousness ("billions are suffering" - "become an optimization process") unless you have some serious achievements of your own to point to. If you do in fact have something to boast about, please go ahead and tell us about it.