the surface area for the point we wanna solder is small and its metal, metal conduct heat well. The heat from the soldering iron will spread faster than not.
THe importance thing is having a soldering iron hot enough and at the instance of soldering, its a simultaneous action of having the lead to the soldering point and having the soldering iron at that point.
Its really hard to spoil the pot, unless wanting to bbq the thing on purposel and having the soldering iron in contact with the pot for extended period of time. And even if extended period of time, either the resistance of the pot will drop or just short out the thing.
If really worried about spoiling pot. Get cheapo pot, $1 a piece type from sim lim tower, solder a few on those first, spoil some first, before using the more expensive pots meant for guitar usage.
heh, we wont learn anything if we dont destroy anything in the process of learning, as long it doesnt burn us badly, everything will be fine...