A pasted sales thread can make a model sound helpful while still missing the real work.
The useful coach needs the motion around the thread: product truth, sales philosophy, the buyer map, what has already been tried, what kind of meeting matters, what should be disqualified, and what tone the brand can actually carry.
Otherwise the system can only write a clever reply. Maybe that is fine sometimes, but it is not the thing I am after. The job is not the reply. The job is helping the seller understand the next move.