I did mention that, yes. From what I read, it was essentially an experiment to see if a reSTIR style integrator could improve quality in lumen GI. That said, I’ve seen relatively little development resources put into it since, as stochastic shadows (which is another sort of reSTIR style integrator for direct lighting) has been receiving a lot more dev time from the looks of it.
Unfortunately, I can’t really speak much to any major quality or technical improvements; I haven’t had the time to pull down a new version since 5.3. I’m very eager to do so, but I’m honestly tremendously excited by stochastic shadows. That said, a neural (or simply improved) denoising solution for lumen would be extremely appreciated.