Interesting thread... I would have to say from experience that it depends...

For instance when someone in a similar situation shares an experience such as a marital situation that was helped by therapy or by approaching something this way... it might inspire a person to have hope where they might not have or to have a different perspective ... but that is lifting a person up to say "Here is a positive thing that happened to me...here is the dragon that was defeated...

but lets say you read something that a person is doing that you perceive as a very negative aspect of a person's personality such as a coping mechanism that a person uses for example... I don't think telling them how you experience that coping mechanism is going to help the person change because they are not behaving a certain way out of lack of ignorance of how it affects other people but because its the way they cope with something going on in their own lives so in that circumstance I don't think change will come from hearing from others experiences.... that is something where a T may be needed to help them figure out what is causing them to use that coping mechanism.... Its like nail biting... I use it as a coping mechanism for anxiety... if you tell me what product you used to make it taste bad or how getting your nails painted weekly helped or how sitting on your hand helped you or how nasty it looks or how many germs you put in your mouth etc etc etc... and how you were able to stop biting your nails. I would be like that's great but as long as my anxiety is high I will bite my nails.

of course above only represents my opinion ....