@substring
The desire for internal BT is esthetic and practical: for one I don't want to buy another piece of electronics which I don't need. And also, I bought this awesome Pi case which looks like the NES which I had as a child, only in very small, and I'm not going to ruin that by plugging a BT dongle into it. Yeah, wired is OK, but my back hurts sitting on the carpet so close to the TV.
A canary test is actually a hidden update to a small number of users, who are usually unaware of their function as a canary, not a method for a protracted roll out of a large update. I feel canary tests are a failure by design, as people running productive systems are used as Guinea pigs without their consent, I have often argued against them and opted for more RCs with voluntary testers who can be readily found for most projects and IMHO are often much more helpful in identifying the problems instead of just being p**sed at the developers for delivering an insufficient product (and they are right!). But no matter, a protracted rollout due to bandwidth reasons is very legitimate and by no means a canary test.
As I basically have no time to be writing this, but have done so anyway, I have no time to get into configuring RetroPie tonight, so maybe I will just check back here soon to find a 4.1 version available for a clean install and so you will have made me just another happy retro gamer dwelling in the memory of a long long time ago, when life was simple: school, computer games, BASIC, and the occasional fight with the parents.
Keep it up!