Seems my questions left unanswered so I honestly want to wish good luck with IC and hopefully smooth GB as well.
The initiative brought by Gondolindrim is very important for our community. The more ergonomic keyboards we have, the better consequences will be there and the more impact on future designs such experiments will have.
I am sorry I was too aggressive and unfriendly with my feedback.
I hope you understand that your first response wasn't even a feedback. I don't know what you meant with it, but to me it resonated as a hurtful attempt to let me down somehow and responding to anything after it was simply an opening for myself to take part in my own abuse. If you were ironic or joking I have no idea as words do not express tone, but to whoever read it (you commend was so impactful that I did ask around what people though about your particular comment) they thought it was a kind of troll-ish diss to the keyboard.
But since you seem to care about what I think and your second response was insightful, let's do this.
First, about the layout being assymmetrical. Somewhere up I did a very in-depth response as to why that is, the TLDR meaning that when typing our hands simply don't move in the same way. The muscular memory of our hands is assymetrical. For more clarification please read above.
For the "overloaded" thumbcluster: the "right" way to do ergo is with curved keycaps. That's what the Microsoft ergo does, that's what the Logitech ergo does. You might agree with me that I can't conceive a layout with curved keycaps in this community because there are no projects to make such keycaps. Also as said in the OP, the true-erogonomics had to be adapted so that the layout was feasible with a base kit. The impact on the optimization is not big.
For people that like modding the layouts I added the two-key options to the thumbs. These sould let you play with layers. This is also done in most ergo splits.
And I will take some liberty to talk about this:
I read that another person wondered why left part has almost classical row staggering. And then I saw reply where the difference was explained but I still think that difference between movement patters of each hand is not so huge that left part should have classical staggering and right part should tend to columnar or even ray staggering. I am heavily satisfied with symmetrical split keyboards with columnar stagger. I don't find drastically differences between my hands that it would required Sagittarius' approach within layout. Yes, I am here only with my experience without any statistical datum.
Understand that, ultimately, the ideal ergonomics are adjusted individually. This is why recovery medicine is such an open-field open to so many speculations and myths. Let me give you a metaphor. On the one hand you have a post-doc MD that has studied 20+ years only so that he could give you a flu medicine or whatever. On the other, you have your grandma saying doctors don't know bollocks and proceeding to give you her lemon-honey-aloe vera tea which miraculously works better than the medicine you were prescribed.
In this spirit, if a symmetrical layout works for you I think it's totally legitimate for you to say that, but I also think you can't back up the information "Sagittarius doesn't work because it doesn't work for me". Like the doctor and his medicine, I have several hundred tests of recovery patients and a few dozen of them actually tried some iterations of the layout and gave us feedback on where their hands/arms/joints felt the most affected, so we could fine tune the results and optimization.
Among the subjects of the data we have were right-handed people, left-handed people, tall people, short people, muscular people, skinny people; as the project's data scientist, I have to give results based on the data which unvariably makes me work with statistics and stochastic processes so that all of these groups are covered in a
statistical way with a certain degree of
statistical certainty. What I can guarantee is that Sagittarius will bring more comfort and less stress on hands/arms/joints/muscles than your common ANSI stagger layout. As such I have tried to respond the feedbacks and questionings in this post with arguments and data back-up, describing phenomenons and results, but at the same time I can't guarantee if the layout will make an individual's hands so relaxed you will ditch all your keyboards for Sagittarius; hence why the layout test sheets.
I **** you not, we even ran "mini-placebo" tests to make sure this layout works -- I gave five friends random split layouts and told them this was our new layout in hopes that they'd just say it's indeed better. And they didn't. This layout passed that test even. Of course a true placebo tests need hundreds of patients and LOTS of data treatment, but you get the idea.
In the same metaphor, your granny's tea is like your symmetrical layout right now. It works for you, it has worked wonderfully so why the heck would you buy a several-hundred dollar keyboard that has this overly-engineered layout that needs a 2500+ word essay to be presented and described? I think that it's totally legitimate you say "well, it's not for me". And I'm okay with that. I'm very conscious Sagittarius is not meant to be the next Alice nor am I trying to be the next yutski.
In the end, Sagittarius is not about
ergonomics, it's about bringing innovation to this community to keep it fresh and interesting, it's about testing how far we can go with a design and how much heart and soul we put into this. So I don't expect you to like Sagittarius, I expect you to respect it for what it is -- which according to this last comment you seem to do, so my deepest thanks for this.