Hey there Mel. I sure appreciate your commentary on that song.. I also think I know who you talking about, but that's not who the grand majestic is. You're talking about the greatest accordion player that ever walked the face of the Earth. I am nowhere near his level. We only share the same initials LOL

Grand Majestic,
Please expand on/explain The Holy Ghost Key/The Holy Trinity. I’ve googled it, but I’m not sure I’m understanding. I’ve taken note of the chord progressions in the vids within your post. Is that what those terms refer to? Thank you for any explanation. I’ve been playing for 50 years and haven’t heard that term. Thanks again!