You got me. I don't know how to parse that ("1p.).

My ignorance is showing. Is there a stack of yank buffers??? Does this p-for-put pop the top buffer, back up before the inserted text, then .-do-it-again and put the delete/yank beneath the last one on the stack? I have no idea what the quotation mark actually does.

Thanks in advance if you can explain how that works to me.