> it only leaked when the flame was out and I was unscrewing it.
> It would flame up, I blew it out, screwed it on tighter and then it worked.
If I read this correctly, it says that the canister started to leak while you were connecting or unscrewing the stove? In that case, keep (un)screwing the stove fast.
What is happening (when unscrewing) is that the O-ring seal is being broken BEFORE the actuating pin has retreated enough that it no longer depresses the valve. This does happen sometimes, as the exact dimensions between the Lindal valve and the stove pin are NOT defined. Some stove/canister combos can do this.
The secret here is to always screw the stove down and unscrew the stove fairly quickly. That way you pass through any possible leaking stage very quickly.
Yes, it is annoying.
Yes, it could be dangerous if done right next to a running stove.
No, we probably have no chance of getting all players to agree on a single standard. No-one will be willing to accept that they have to change.
> I'm still waiting for someone that overflows their boiling pot onto the canister,
> which raises temperature of canister, which could produce a much bigger flame.
Be very careful about what you wish for. There have been accidents with over-heated tanks, resulting in burst tanks and people getting 3rd degree burns over a significant part of their body. I have photos, but they can stay unpublished.