That link is talking about planting a banana sucker, not seeds.
Soaking the seeds kind of slaps them out of dormancy, and that is why we do it. Here is another eHow link referring to seeds (in general) that explains it better than I can:
Is it a Good Idea to Soak Seeds Before Planting? | eHow.com
One of our experts here just recently mentioned his way to seed success, which is nicking the hard coat of the seed (just until you see white) and soaking for two days in a Superthrive mixture then planting. He said if the seeds are viable they will sprout quickly with this method. I will be trying this with my next batch!
~JaNan