Jane, I agree with everything you said about physicians and/or hospitals mentoring residents.  I was trying to frame an answer along similar lines myself.

There is one thing missing from your discussion, and as much as I hate to refer to insurance -- you didn't mention that.  I am not a litigious sort of person, and I would hope that moms who are that dedicated to nursing that they are paying for the consultations would also be less suit-prone.  But the fact is that
here in the USA, people are very quick to blame "professionals" for whatever goes wrong, even when the professionals are trying to improve a correct a previously existing condition.

  In the hospital situation, we have nursing students and medical students.
 We also have NP students, SocialServices trainees.  Etc.  The nursing 
students are accompanied by their nursing instructor, and the schools 
maintain a certain liability for their actions.  I am sure there are also 
arrangements made to cover the other types of students, either by the 
institutions from which they are earning their degrees, or by the hospital.  
Otherwise our hospital wouldn't let them get to the pts. bedside.

Who assumes liability for an LC trainee?  How many LC's even carry 
insurance against liability for themselves, much less are able to provide 
coverage to others?   

Were I to mentor someone, it would have to be someone I trusted to 
provide the same information I would provide myself.  Or to discuss 
variances of information with me before presenting it to a client.  Even as in
 the hospital, I expect the LVN's and CP's who are working with me to 
continue the plan of care I set out for the day; and as I discuss situations/ 
patients with the "official" LC's, before initiating a careplan other than "the usual."

Chanita