For some reason XMR seems to stay less coupled to BTC than other alts...
Numerically that hasn't really held true. I've looked the data and both XMR and most other alts are highly correlated with BTC (and each other). XMR is actually more toward the "more correlated" end of the spectrum.
There are maybe some exceptions but for the most part if you are buying or holding any in particular, you are either betting on a decoupling in your favor (over some time horizon might be short or long), or hoping that the relatively small residual is in your favor (of course both can be the case).
I am either defining something backwards or just fully mistaken in my appraisal. What I notice is when alts sell off during a BTC rise Monero tends to do so with less momentum. This is the case now. While other alts are down 8-15% XMR is down 6%. And when alts rise WITH BTC Monero does less so.
But it could certainly be some sort of confirmation bias. I have done no spreadsheet or real study. I do not trade on it. I do not really trade...