Write as well as read; tell as well as show

As the title of this post suggests, I'm going to have my say about two of the most common bits of advice doled out to wannabe writers (of which I am one), namely: read as much as you can, and show, don't tell.
The read one is easily ticked off, because unless you actually start writing at some point, all those fantastic ideas and characters and plots are just going to stay imprisoned in your head. In my case, I find reading is kryptonite to my writing: I struggle to find my own voice and ideas if I'm immersed in (and especially if I'm enjoying) another writer's books. I'd also say that in the experience I have to date (4 books, going on 5), you learn an immense amount on the job and through self-editing. So reading helps, but you can always read more: if you want to write, write.
Show don't tell is also a very common piece of advice, and also much debated. I find incluing - showing not telling - a lot of fun, but also very tricky to pull off. It's great to see a world through the eyes of the characters without the constant 'travelogue' of some narrator, but it can be overdone. I've just reviewed The Quantum Thief which is great but could be greater if it gave the reader a bit more of an idea what is going on.
I found an example I really like of what might be called 'layered incluing' from Thin Air by Richard K. Morgan, so here it is. And spoiler alert: if you've not read the book, this might give a few (low level) reveals.
Hakan Veil is talking to Hsu/Xu/Gradual, a member of the Chinese triads from Hellas (they're on Mars) who is trying to infiltrate the organised crime scene on the Mariner Strip/Gash. Veil and Gradual have a disagreement and almost come to blows. Morgan says this (p. 57):
"She twitched back, hands rising, ready. Most of these Crater triad guys have some moves; their 489 wouldn't draft them in for duties in the Gash if he didn't think they could handle themselves."
So, here is a bit of incluing: what is a 489? The context does a great job of showing us through Veil's internal monologue without telling us directly - we can easily guess that a 489 is someone (he primes us it's a male) who is in charge of an operation, some kind of chief. This in itself is a great example of how to set up the context to make the incluing seem natural but informative.
But Morgan goes further. Things cool down enough for Veil and Gradual to talk, and Veil ends up making a demand which he signs off with: "Now you go back and tell that to your 489, because we're all done here." (Also p. 57).
This is also good, because it not only sets up tension in their relationship, it also gives the reader another shove that their assumption from earlier was correct and a 489 is some head honcho type.
To which Gradual responds (p. 58) "Mr Veil, I am the 489 for this context." Only then does Morgan actually tell us what a 489 is, a full page later: "She looked back at me out of lenses gone suddenly transparent - almond-shaped eyes hard and watchful but offering no threat that I could discern. 489 - traditional triad notation - command enforcer. She'd been central to my dealings...[etc. etc.]"
This is showing and telling, and that's why I think it works really well. It gives the reader everything they need to work stuff out for themselves, but it doesn't leave them fumbling around in the dark. It also has a neat twist in that Gradual is a female 489: Morgan wrong-footed us from the off.
Incluing is hard, and reading can offer great lessons in how to proceed, but as I said at the start of this post: unless you write, you'll never learn to do it for yourself (or appreciate how difficult it is).