You can give whatever advice you want to give. I usually qualify it if it is not something I experienced, but something that is typical, like "You might try NILIF (Nothing In Life Is Free). You can Google it. I don't use NILIF with my dogs, but lots of people here have found it very helpful."
Telling people they are wrong, kind of goes over like a ton of bricks sometimes, especially when there are only a finite number of things that are totally black and white. Most things, somewhere lay in the realm of opinions, and while some opinions may be better constructed, more popular, better explained, they are still opinions. And even if you are 100% sure you are right and they are wrong, this:
"What I have experienced is that a healthy dog will not starve himself to death, if you pick the food up after 15 minutes and then wait until his next meal time, he will probably eat it eventually."
goes over a whole lot better than,
"You're wrong, spicing up a dog's food to get him to eat it is just going to make him a picky eater."
If you tell enough people they are wrong, then someone will probably start a rude-thread to complain about how people come across.
Bear Cub, Hepsi-Pepsi
Cujo2, Karma Chameleon
Ramona the Pest, Kojak -- who loves you baby?
Tiny Tinnie, Susie's Uzzi, Kaiah -- The Baby Monster.