I had an interesting experience the other day. I have been using split keyboards for years, but only recently began using a Kinesis Advantage 360 Pro as my daily driver for work; I am so use to the layout now, that in instances where I have to use a non-split, or even my older splits, my fingers fail me entirely - like my brain forgot how to type, my thumbs eagerly searching for the thumb cluster that isn’t there.
This is one of my worries with adapting to a non standard layout. My work means I’m constantly on different devices and machines so I need to be able to use a normal keyboard and windows. Using Linux is already making the windows part frustrating.
If you’re constantly switching, you have have issues.
If you’re needing to physically type on different machines, you could try hasu’s USB2USB device, which is a programmable dongle that sits between the keyboard and computer and applied whatever layout you want.
Piggybacking on this comment, I made one of these, works great but I don’t use it anymore. If anyone wants it feel free to PM me. (I guess we’ll learn how PMs work on Lemmy…)
My speed on row-staggered QWERTY non-split keyboards is pretty much the same as before. Maybe it’s because I switch to Colemak a few weeks after switching to split columnar keyboards. I think that they are just separate in my head now. Similar to how learning to use split keyboards didn’t erase my memory of how to ride a bike.