IMO learn to swim in the pool.
A balance of both is perhaps best, which is what industry PhD holders have.
There's a quote I kinda forgot, but it goes something like:
"Did you experience the same thing 10 times, or did you experience 10 years worth?"
And I think this is true for a lot of real world experience, you don't necessarily have 10 year of it even though you've worked 10 years, you have 10 times the same experience.
I've found a few programs that are open to considering part-time candidates, but they are few and far between, and most of the ones who consider it still strongly recommend against it.
Went (going?) through it. My wife is doing her PhD. From 2 really good incomes to one stipend. We don’t live in campus housing so it’s more expensive (savings helped here initially), but we do know of others there with their spouses and some even with kids that are doing good. I found a job after getting here which helped.
FYI for others wondering about the same, I wouldn't wait the full 10 years unless you are going to study something very industry adjacent like software engineering methodology. I've had to spend a lot of time relearning anything theoretical.
I bet the sweet spot is 2-5 years.
You're right, no trials on methodology that resemble something like clinical trials. And of course the reason for that is it would be incredibly expensive to even run a reasonable pilot (two small teams head to head implementing a realistic system), and if any organization has actually gathered data, it would be the crown jewel of proprietary knowledge. Not something you would ever open source.
The only thing I can say is that an immature field is one with opportunities left. If you can figure out how to jump the hurdles you can make a huge impact.
PS, an example of a bug study like I mentioned (this isn't even that great but just goes to show how hard any sort of software study is): https://www.google.com/amp/s/blog.acolyer.org/2018/06/28/how...