I have a mid 60's Guild 12 string. I play light strings and tune to concert pitch. I used to tune down a step and capo. My luthier at Elderly Instruments asked me why I did that. He said that the instrument is over 30 years old. If the neck was going to move, it would have done so long ago. I suppose if I went to heavier strings, then I might tune low/capo, but my old Guild has an action to die for, and a voice that is amazing.

Appollonio might be a different matter. Nick uses very little bracing, so that might make a difference.

And I know what you mean by the weight of these Guilds. Try doing a four hour, standing up gig with one.

Le gach dea-mhéin,      

Mick