(Thank you, Ron.)

Ron Olesko has just said something that's very important to the process: the thing about a reliable engineer. They will know what mistakes can be corrected. Some can and some can't.

Rule one (well, a rule anyway) in studio--with recording--is NEVER throw anything away. Another thing to keep in mind is that you best record stuff in key. That is, A440 or something relative, because if you decide to put a keyboard guy/gal in there and they are overdubbing, well, if you are 1/4 tone out, the twains will never meet.