Yes, tuned lens is an excellent tool and generally superior to the original logit lens. In this particular case, I don't think it would show very different results, however (and in any case the logit lens is only a small part of the analysis), but I think it would be interesting to have some kind of integration with TransformerLens that enabled the training and usage of tuned lens as well.
This is a cool idea, and I have no doubt it helped somewhat, but IMO it falls prey to the same mistake I see made by the makers of almost every video series/online course/list of resources for ML math: assuming that math is mostly about concepts and facts.
It's only about 5% that. Maybe less. I and many others in ML have seen the same videos and remembered the concepts for a while too. And forgotten them, in time. More than once! On the other hand, I've seen how persistently and operationally fluent (especially in ML and interpretability) people become when they actually learned math the way it must be learned: via hundreds of hours of laborious exercises, proofs, derivations, etc. Videos and lectures are a small fraction of what's ultimately needed.
For most of ML, it's probably fine--you'll never need to do a proof or do more than simple linear algebra operations by hand. But if you want to do the really hard stuff, especially in interpretability, I don't think there's any substitute for cranking through those hours.
To be clear, I think this weekend was a great start on that--if you continue immediately to taking full courses and doing the exercises. I'm a top-down learner, so it would certainly help me. But unless it's practiced in very short order, it will be forgotten, and just become a collection of terms you recognize when others talk about them.
I actually went through the same process as what you describe here, but it didn't remove my "transhumanist" label. I was a big fan of Humanity+, excited about human upgrading, etc. etc. I then became disillusioned about progress in the relevant fields, started to understand nonduality and the lack of a persistent or independent self, and realized AI was the only critical thing that actually was in the process of happening.
In that sense, my process was similar but I still consider myself a transhumanist. Why? Because for me, solving death or trying to make progress in the scientific fields that lead to various types of augmentations aren't the biggest or most critical pieces of transhumanism. One could probably have been a transhumanist in the 1800s, because for me it's about the process of imagining and defining and philosophizing about what humanity--on an individual organism level as well as on a sociocultural level--will become (or what it might be worthwhile to become) after particular types of technological transitions.
Admittedly, there is a normative component that's something like "those of us who want to should be able to become something more than base human" and isn't really active until those capabilities actually exist, but the process of thinking about what it might be worthwhile to become, or what the transition will be like, or what matters and what is valuable in this kind of future, are all important.
It's not about maximizing the self, either--I'm not an extropian. Whether or not something called "me" exists in this future (which might be soon but might not), the conscious experience of beings in it matter to me (and in this sense I'm a longtermist).
Will an aligned AI solve death? Maybe, but my hopes don't rely on this. Humanity will almost certainly change in diverse ways, and is already changing a bit (though often not in great ways). It's worthwhile to think about what kind of changes we would want to create, given greater powers to do so.