I've basically lost the ability to do joined-up writing. I can invoke the muscle-memory, but the output is effectively useless noise. I suppose if I took the time to draw a picture of the characters I could accurately reproduce the way I learned to write joined-up when I was 9, but the bandwidth of that is so appallingly low that it's impossible to think and write at the same time. (Indeed, this is why I've used a keyboard to write for as long as I've been allowed to.)
In real life, when I use a pen to write on things, I use block capitals. It's marginally faster than bit-bashing cursive, and is much more legible (which is usually important, because if I'm writing on something it's nearly always a label of some kind).
I've never really been able to read an arbitrary person's[1] cursive handwriting. When I see people do it it feels like there's a bit of my brain missing. Sure, if I pick my way through I can make an educated guess at each letter and assemble them into words, but I wouldn't call that reading. It's a process more akin to decoding binary coded ASCII.
[1] There are exceptions, but most of them were in my class when I was 9.