Following on from that, I have pushed my v52 DCTL implementation, as I mentioned in the meeting. But it comes with the caveat that it does not yet fully match the Blink. i am working on tracking down the cause of the discrepancy, and will push further commits.
This commit should make the DCTLs match now. It took a while to track down, but I found a typo that was messing things up. I also realised the 500 nit version was still using the old cusp tables from the 540 nit one.