no critical problems found in model theory doc

Hi Pat,

I've been looking through the model theory doc; got about 2/3rds of the way 
through before my concentration started to wane and I figured I better stop.

No critical problems.  I advise you not to read the attached review copy - 
there is nothing there that needs immediate attention (in my judgement).

I marvel at your powers of telepathy.  I kept finding myself writing a 
comment and then going back to remove it after I'd read a bit further.  I 
left a few in to amuse you.

I think the only major concern I have is the lbase appendix, but that is 
something we can discuss later.  I guess it comes down to my not 
understanding why its there.  Occam says take it out and put in the lbase note.

You have done a fine job under considerable time pressure.  Thank you.

Brian