You could not bend it, so only use it for straight lengths.
You can actually. 15mm is easy and 22mm takes a few trys to get right every time.
Won a few bets on that one years ago but generally it is not advisable as it thinned too much.
Copper years back was much thicker and softer than it is these days which is probably why it has lasted so long with no problems. A few times i've come across screwed copper (i still have a bit and a couple of fittings lying somewhere that i cut out of a job) in early 1900's big houses which would have been top quality work at the time. Even up until the 50's early 60's the copper was still thick and strong and the brass fittings were real bush brass.
Into the 70's and things are starting to slim down but thinwall excepted, the pipe is still decently thick.
When i started working (73) i remember doing a new build on a bungalow and pulling a 20ft length from the tee for the sink right onto the ballcock (i was told to do the Belgian burl, rough eh:lol
no kinks just easily hand bent.
By the late 80's the imported stuff was coming in from Europe (the stuff screwfix still sell). Harder and thinner and cheaper. Definitely a different composition. Bang it on the ground and get the orange dust out.
Now most pipe sold is nothing like the pipe of 30 or more years ago and buy anything over 35mm and it is thinwall.
A bit like a kit kat is still a kit kat but if you are old enough you now it is half the size.
The world is now run by accountants. Everything, even once good brands, is made for the lowest possible cost with the maximum profit. We are being fed shyte and swallowing it.
The water up here is very soft so copper failures are still very rare but brass is different.
