Mark Clark:

Thanks for the observations on the chords, especially the second one. The Bm7+ (excuse my notation if it is wrong) sounds plausible given that the chord is from a song that also has a(nother) bastardized E chord (E F# B) thrown in for good measure and is (loosely) based on the I,IV,V blues structure. In case you're interested, the chord is from Robin Trower's song, "About To Begin", from the album "Bridge Of Sighs" (my apologies to folkies and bluesists but I recently bought an electric guitar and I'll try to play ANYTHING if I think I can figure it out- in defense of Trower, however, you can tell he's been influenced by the blues, as most of his ilk were/are).

What you call the GMaj7sus4 I have to take blame for as an accidental discovery propelled by my perversely ignorant musical thought processes. I had always thought the root of this chord as being C, due to C being the bass note (and hence, the first note to be played when the chord is strummed) and therefore, the chord itself as some sort of C "mutation," but your explanation in your post about chords changing names depending on which note is tonic broadened my vista, so to speak.

Thank you and regards.......Neil