It's like asking about the chicken and the egg. If we try and analyze, looking for a conclusive, or logical answer, it maybe an ongoing debate. I often struggle with this because I'm the type who likes things logically explained in black, and white terms, yet it's never that simple.
So that said, maybe there are multiple answers, or at least two, or perhaps none. If you can harness the potential of your mind's power which most of us can't, then mindset rather than routine came first. Logically I think mindset, which is all encompassing must be the most logical conclusion. But maybe not, but why not?
Probably because not everything is tied up neatly in a pretty red bow, which would be logical, much like it shouldn't be logical that bumble bees fly. Based on physics they shouldn't, yet although their body is way too big for their wingspan they blow that reasoning out of the water.
Here's a thought, what if not knowing whether it was mindset or routine was part of the plan. Maybe the discovery of this was dependent upon trial and error, in addition based on human nature. Some things are better understood and appreciated if more effort is put forth. Hmm.?
Understanding why anything happens takes will, determination, and belief. With time a revelation will occur producing some kind of outcome, in addition creating awareness and clarity, but beyond that, it develops intuition, strength of character, and the will to persevere. This is a good thing.
I guess the answer to which came first, mindset, or routine is inconsequential because they both are one in the same, much like identical twins, in many ways needing each other to endure.The moral of this story is that trainers have to wear many hats other than just trainer. Legit trainers will always go the extra mile finding out the why about everything to the inth degree. Does yours?