Yes, totally. I love questions about craft, like, A LOT. (I finished my master’s in writing this spring, which was pretty much six years of asking craft questions.)
How much time I spend on writing in a day depends on what part of a project I’m working on. The start of a project varies wildly - some days I’ll spend a couple of hours writing a scene I’m excited about or taking a shit ton of notes, other days I won’t write at all except for in my head. When I get my footing in a first draft or revision, I probably average between 2-4 hours a day. When I hit the climax of the story (especially in a first draft), I tend to try to get it all done in a rush, spending a few days holed up in my apartment, mainlining Dr. Pepper and working on that project 12-16 hours/day.
Also, I usually have at least one random day in a week when I need a break from the project and get zero work done in favor of marathoning a TV show. I used to beat myself up about it because OMG UNPRODUCTIVE PERIODS NOOOO *HUFFLEPUFF GUILT* but that break is VITAL. I get hopelessly emotionally over-invested in whatever I’m working on, so my brain needs breaks mid-project. If I try to work straight through, my emotional energy meter bottoms out and I crash around the 90% point in the story. (That happened with CFLC between chapters 8 and 9. I felt like shit for a few days before caving and watched most of Orange is the New Black. Then I was back to writing.)
I also take a lot of break days between projects, because decompression is good. I worked on my thesis novel for 3-4 hours yesterday, but today I’m watching Dexter and giving zero fucks, and it’s wonderful. (I’ll start to get noticeably out of sorts if I spend longer than a couple of weeks on break, though. Writing keeps me sane in a very literal way.)