I just got an Iwatani Torch. I can already tell this is an amazing, professional quality piece of equipment. I got it for searing sous vide meats, so I will probably use it at least once a week. It says to release the butane canister from the torch when you are done using it for the day. Do I really need to do that, or are they being too cautious? Does anyone out there leave the butane canisters connected?