That's not what I said.
I do know that my PS3 got really hot and I did perform repairs on it myself so I've had hands-on with the PSU. The fan wasn't the issue, I had the version with the extra blades, turned out I needed new thermal paste. Anyway there really isn't anything special about the PSU other than the fact that it's placed inside the console.
There it is in the middle:
You're implying that external PSUs are the obvious engineering choice..and the fact that Sony decided to go internal, going by your logic, means ?