I would guess this depends on how you define "install MK8", "dl the DLC", "run said game" and "without jumping through the all the loops". Yeah...I know this bounces your question right back at you, but how you do things is obviously important for the outcome.
Short version: if you install haxchi and then coldboothax correct, you won't need to jump through hoops afterward (I can now turn on my wiiu and after cbh has done its thing, directly play what I want from the menu). If you don't want to install things on your wiiu, you'll need to jump through hoops, yes. And that's independent on whether or not you use the brazillian method, loadiine or mocha/rednand.
Let's stick with the (in my case not hypothetical) case of mario kart 8: I bought that disc when it was new. I used a program to dump it to SD, and then another to install it to USB (I forgot the name, but there's now even a single homebrew app that does both these tasks). This worked fine. Then I got usb download helper and a certain site. Used that/those to download the DLC for mario kart 8 and installed that to USB as well. Result: I can run the game AND the dlc. The only thing I missed was the savegame*, but I suspect even this can be overcome by using saviine.
*note: do NOT attempt to move your mario kart 8 savegame from the system to your USB. It'll work...but it will overwrite the mario kart 8 (and the DLC) on your USB drive.
