"bill333 can you give us a non-mystical, technical explanation for how removing the chassis top of a component would cause those audible differences (or releasing of the capacitor)?"
I have no technical explanations for this, and no interest in finding any. There may be people out there who enjoy observing scientifically unexplained phenomena and constructing theories to fit them, but that's not the hobby I'm engaged in. I'm trying to create great music listening experiences. Simply put, I don't see how having a well explained system is going to give me better sound. OTOH, if you have practical ideas on how to get better sound from my system, I'd be glad to hear them...
"(BTW, I’ve had the top off some of my equipment before - pre-amps etc - for different reasons and...no...it did not change the sound)."
There could be any number of factors involved in your not hearing a change in sound. Without being there to hear for myself, and subsequent experimenting with your system and room, I really can't say what happened. The most likely explanation is that some component or components in your system are closed down to the point that upstream changes can't easily be heard.
But let's get to the point of your post. You're not here to help people get better sound. Having read through your posts on this thread, I can't find a single instance of you doing or saying anything that would help another person improve their system. You're here to cast aspersions on anyone whose methods who don't fit into your mental model of how things work. Let me be clear in saying that my experiences are my own, and are posted here in the hope that others can benefit from them. These are things that have worked for me. If you, or anyone reading this, tries these methods and benefits from them, I am genuinely happy about that. If you choose not to try, that's ok too. But I have no interest in trying to fit my experiences into your dogmatic belief system.