First, I want to mention that this survived a Monday, which is awesome. This is the First time I was able to do my full catch up using keyboard, I do still sometimes reach to my mouse to cut-and-paste and quote and so on.
The basic mechanics of catching up are very close, to summarize here are all the bugs (+ a new one) that we want sorted.
I do feel this may become a core feature, cause with this component J K turned from unusable for Sam to indispensable to Sam, which is a big jump in my hierarchy of needs.
Bugs to fix:
Up navigation with K does not resume at end of post, instead goes to top of post. Repro is to make a giant post, a small post, hit
k on giant post.
K does not work on post #1.
Debounce bug is severe, if I hold K or J down stuff queues and gets super weird. (when you want to reach first post and there are only a few, then holding K seems easiest)
Transition effect can be done smoother and with less CPU / JS. To be honest, I notice almost no issue on Firefox on my monster dev machine, but on my old laptop with Safari I notice this big time.
Once you get sorted can you enable the theme component on all themes on meta? Then @zogstrip and @eviltrout who also like using these keys cause Vim, can test it.