there are 3 actual ways....the 12MT i mentioned, adaption by simply riding the bike, which takes some miles, and by doing it with tuneecu. I suppose dealers have that option with the triumph app too. I think champ87 may be talking about the latter. Not sure whether any of them do anything different than the other, but i do know riding the bike never seemed to make it adapt like the 12MT tune did.
The 12 minutes is the correct time. It's in the manual, it's mentioned a million times in these forums. I didn't just come up with that myself. Not sure why the fan must kick in or how the ECU looks at any of this, but thats the way it's done.....do not touch the throttle, count 12 minutes from when the fan kicks in, then turn bike off for a minute to let ECU do it's thing as it does after the key is turned off. Disconnecting the battery....i dunno. I can't tell you if that erases the adaption, but i would think not. It erases things like fuel amount but adaption i would think not. I would however do the 12MT after disconnecting it if anything changed in the way it runs, assuming i knew adaption was optimal before i disconnected it.
As to air temp, i wouldn't do it in warm weather unless you put a fan in front of the bike pointing at the radiator. It can get VERY hot in the approximately 25 minutes this takes, and i have had smoke come out of the front of the engine near the end ! So I'd do it on a cooler day if possible or in the morning. As to doing it when the temp is closest to what you ride in, no. The bike has a air temp sensor and it will change that all the time anyways. I think adaption encompasses some things that do not change all the time when riding like that. The fact i rode several hundred miles after loading the map then did the 12MT with a major change tells me there are things that are more permanent than others and that adaption thru riding does not change, or at least not easily but the 12MT does. I have to technical understanding to back that up, but my experience with this tells me I must be right to some degree....it just makes sense.