THis no-soap stuff is pure horsepucky.
You can wash a cast iron pan with soap and water, it will not hurt the pan. It may thin the seasoning coating a bit, but using the pan will replenish it.
I don't always use soap and water though, mostly I use plain hot water and a brush. The water should be as hot as you can make it to cut the grease and dissolve cooked on food. It'll also kill most of the cooties if you can get the temp up towards boiling. The water from my kitchen sink comes out at 170 degrees, so it's real close to boiling already.
One of the big problems with not washing your cast iron out from time to time is that burnt in food particles can go rancid for one, and they can also begin to harbor other bits of nastiness. They can also impart an odor or flvor to other foods.
Sometimes a cast iron pan will get somethign stubborn on it and you must resort to abrasives to get rid of it. No problem. Even if you polish down to bare iron, turn on a stove burner and coat with the oil of your choice...I use butter as often as not. cook that stuff down at medium heat for a while. Recoat, lather, rinse and repeat as the saying goes. Then use the bastard. It'll reseason the spot in a matter od days of regular use. I reseasoned two pans this way this past weekend.
You can also buy Lodge cast iron pans pre-seasoned from the factory. Walmart sells them that way as well as other outlets.
My wife and I typically give a cast iron fry pan and lingerie as a wedding shower gift to new brides...kind of a punishment and rewards thing.
We have a wide selection of pans available to us including some expensive AllClad stuff. I'm moving more and more to the cast iron. Once seasoned it is anti-stick, even heating, easy to clean and just generally superior to all other options. Go easy on the cleaning, but a bit of soap and scrubbing from time-to-time won't hurt them.
The advise to flip the pans over in the over is pure gold. Most modern oils tend to pool and gum up rather than cook down and coat the pan. giving the excess somewhere to go is a good idea.