As I said in the chat, if your DK skills are solid, you're 90% of the way there with no hammer. So it's not too much of a surprise that you were able to get that score.
No-hammer is actually best used as a training exercise for players who AREN'T that great on the rivets. It makes you learn to pay attention to certain things that you wouldn't necessarily pay attention to in regular games.
The problem with hammer-allowed rivets is that you can play on autopilot using a pattern and never learn a lot of things because you're never forced to. But with no-hammer you have to think on your feet the whole time on literally every rivet screen.
In your case though, you pretty much already have down all of those little bits and pieces that players pick up through no-hammer practice.
Having said that, there are some no-hammer specific strategies.
You already get that the whole game pretty much boils down to the fight for the two rivets on the top right. That's the most important thing. The top left ones can be a pain in the butt too though if things develop a certain way, believe me.
Ross mentioned trying a "reverse weave" approach in my chat today (I said some things in response, not knowing that my mic had popped out, so only my wall heard them). Anyway, a couple years ago when I was really focusing on no hammer I tried that, and it's definitely a viable strategy. Depending on which way things break, you can clear a lot of screens that way. It is not unequivocally better than the "up-the-left-side, over to the right" though. You run into problems with it and a lot of VERY EARLY deaths when you get bottom-spawners. I don't know, I might look into it more.
One thing that's important to develop in no-hammer is the right philosophy. You have to accept that no-hammer is extremely luck-intensive, and as a result, it's often better to say "screw it" and do super-risky things that MIGHT kill you now in order to prevent what is likely to develop into an impossible situation that will DEFINITELY kill you later.
Some examples of what I mean:
- Waiting at the top of a ladder even though there are one or more firefoxes directly above (especially important when time is running out)
- Willfully going into situations where the only way to live will be a wall-jump that works out
- "Boxing yourself in" between live firefoxes knowing that you're going to have to jump over one of them
etc.
If you take that approach, you'll have a lot of terrible games where the risks gets you killed early. However, you'll also have games that go further than a super-conservative player will ever be able to go, because without a little gambling, the firefoxes will simply take hold of that top-right area too often and time you out. So if you take risks and are having a good day and happen to get lucky several times in a row, it starts to add up. After all, you only have to get through 21 rivets!