Classic beginner mistake is applying too much heat and having the solids, fat and water separate. Usually the dinner can be rescued by mixing in something acidic, e.g. squeeze a bit of lemon in there, or add a splash of vinegar and then stir vigorously. As a matter of fact, one of the beneficial effects of adding wine is that the acids support the smooth dissolution of the fats and reduce the chance that you'll end up with glue floating in water.
Gradual melting at medium heat on the regular kitchen stove and gentle caressing of the mix with a spoon usually avoids this issue (at least for me). The reason I like to do this on the stove is because it is much easier to control the temperature than on the burner. Once the mixture is melted and starts bubbling lightly, it is ready to server and I plop it on the burner.
Those are OK- although I much prefer the cheese mix from my local cheese shop. My NOOOOOOOOOOOOO is about the packets full of additives and strange tasting additions, with all the other ingredients thrown in.
Our local cheese is so tasty- and one great advantage is that the 'fromagerie' lends you all the 'caquelons' (fondue pots) and forks for free if you buy from them - great for large parties as we often have here. Had a fondue for 43 people the other day.
Tom I love Paprika crisps though- and salt and vinegar too.
One just fills the container pot with cold water and leave it overnight - the old cheese comes away easily.
The pottery style pots can be dangerous - the bottom can overheat and fall away - spilling hot melted cheese.( Didn`t Migros just recall all their pottery Fondue pots for that reason?)
Because everyone loves the burnt cheese left at the bottom, people are inclined to leave it heating when the cheesey part is finished - and this also causes the pot to crack. Metal is best, and safest, and longer lasting too.