I don't think I'd change a ceiling rose without switching off the circuit - and checking all the wires in the rose were dead.
Obviously your advice is extremely good - particularly the checking (even after switching of the circuit) that all wires are dead!
Some years ago I failed to do that & got a very nasty jolt from a still-live connection - which wasn't a good thing as I was on some step-ladders on the landing at the top of the stairs!
I was trying to replace the ceiling rose of the landing light &, as you do, put the light on & then pulled the fuse ensuring that the light was now disconnected/isolated.
To cut a long story short, I discovered that this upstairs Light (because of 2-way switching) had been fed from the downstairs light cct & not from the upstairs light cct. However, for convenience, it had been installed using the upstairs' Neutral & the Rose had BOTH the upstairs Neutral & Line connected (although the Line connection was not feeding the switch - just being used as a connection point).
Hence, although I had isolated the "active" Line (from the downstairs' cct) the "non-active" Line (from the upstairs cct) was still live!
I think, at the time, I said something like "Oh dear how unfortunate"!!