[ccp4bb] practical limits of MR?

[Nat Echols]

I had a debate with a coworker about using MR in desperation and I'm 
curious what the most extreme case is where a very different model was 
used to solve a structure.  This could be highest RMSD, lowest % identity, 
or most incomplete model.  I'm also curious whether homology modelling has 
ever been useful for this.  (I'm pretty sure I've come across papers 
discussing this last concept.)

thanks,
Nat