In your example, you contract with the company to have a fictitious character to entertain the kids. Mickey Mouse can be duplicated, Susman cannot and is an individual. If Mickey does NOT come, you have a breach of contract. This does NOT apply to law firms since you retained the Firm, not Susman.
There is a difference. It is not an apple and apple comparison.
Shananigans... If I were to hire the Johnny Cochran firm (when he was alive) I would get John Doe, esq. that worked for the firm. Same thing here. SS has been in the spotlight in the Dodger case - thats good for the law firm either way. We have great attorneys from SG here. We're good. IF you can do better than Nelson or Sargent did last week- then so be it - however, I DOUBT IT.