1. Write down the problem. 2. Think real hard. 3. Write down the solution.

This is a joke of course, but much of the real 10xness is invisible. It certainly doesn't look like typing. Perhaps quite a lot of it occurs off screen, in conversations, whiteboards, on the computers of colleagues. I'll give you two analogies:

In some ways it's like one of those "bullet hell" shoot-em-up games, but played out over weeks or months. There are all manner of mistakes that can derail a project but only become obvious later (e.g. poor dependency or architecture choices), and there are all manner of techniques that may let you skip a section or avoid a whole category of problems, perhaps at the cost of requiring more immediate skill (e.g use of higher level but unfamiliar programming languages like Haskell or APL). Someone with 10xness dodges all the bullets and takes the correct shortcuts, while people with less talent and experience mistake the one for the other or don't see it coming.

Or there is "bug sniping", which I think is the place I've been able to make "10x" contributions: it's possible for your colleagues to be simply stuck on something, consuming a lot of time for no progress. Maybe they can manage a workaround, but at an efficiency cost - like people driving slightly broken cars which you have to open the passenger's side first to unjam the driver's door. This is the field in which puzzle-solving ability really helps. It's just that the puzzle has been created accidentally by other developers or yourself.