I really do not think you two are in alignment on terminology (client and router).
I think there is a problem in the original version cited by Rich. The user is left with a router behind a router, and the instructions to move the physical device are located in the "Optional Next Steps". This is a potentially bad configuration as it is very probable that the LEDE device is in the same subnet as the primary router (see more below). Alberto is interpreting this to be a "client", and the config instructions he offers are basically a wired "Dumb AP'.
I do not believe that most new users are looking to set up a Dumb AP (or bridge) out of the box, but as we collect no data on devices or usage from the community, it's a guess. In the absence of the same i think the QSG should focus on the absolute minimum needed to get a user on the current Release version of firmware and guarantee it works. The device is delivered as a Router, so that seems to be the most basic approach.
The DD-WRT approach has the user:
1 - Download firmware to a "Client PC"
2 - Go "Offline" - Connect the PC directly to the device to be flashed, flash the device, gain access and set basic info like password, LAN IP, and time zone and basic wireless.
3 - Shut down PC and router, reconfigure the user hardware environment (remove and replace old router) and connect to the internet.
Between the shut down and reconfigure we should avoid the router behind the router and IP issue. While not ideal, double nat will work and connect in most cases if there is no IP subnet conflict between devices. Unfortunately there are about 1/2 dozen major brands at 192.168.1.1. I have advocated elsewhere we change the default LEDE address, however the 3rd item above should avoid the issue, and not require the user to set fixed IPs (As DD-WRT has suggested in the past).
The prerequisites can indicate that the "Router" is the expected outcome, however we can also link there and as a note after item 2 above to instructions (some other item number in our instructions) for device configuration behind the primary router (Wired AP and bridge variations).
Related, I would like to clarify that single port devices are, by default in LEDE, configured as a "router". All the LAN side stuff is the same. The only real difference is there is no WAN physical or logical connection delivered by default. What ever flashing instructions for these devices should work up until the point we connect the device to the internet (3 above). At that point there can be a "Single port" bullet item with a link directing the user to another page for configuring the WISP\STation\Hotspot connection. (I have test Rich's instructions twice for this now).
It may be less confusing to combine the QSG and standard flashing instructions into a single page. I realize the benefits of the modular approach, but not seeing that the module is accessed elsewhere. That said, the "Standard Flashing Instructions" should be the same for a user moving from factory or LEDE to a version of Trunk, but require different subsequent handing (SSH, install Luci, etc). While we do strongly discourage this use, it may be the only approach for a user to get their NEW device operating on LEDE, at least until the next Release version. (warrants more discussion)
I agree that Rich's link is a better starting point. I also agree that SQM, while a great tool, is not a minimum requirement and can be moved to "Optional Next Steps". I do not think we need any UCI instructions and agree that checksum is important, but can be linked to a separate page (and be made modular for other instruction sets) to make the QSG more "Quick", at least visually.
Regarding terminology, I would like to suggest that we consider adding a new WIKI section for "Terminology" (Definitions). With the large international audience, there are many terms that do not translate well. Examples:
- bridge, wireless bridge, repeater bridge
- WISP, STAtion, AP, hotspot
Clarity in these definitions would better help us align terminology across wiki documents or even to direct forum posters for clarification of their configuration. I am amazed at how challenging it is to understand what some users are trying to accomplish.