First off, the guy said he ALREADY has had multiple conversations with the guy that is not necessarily going to be the one making the hiring decision. Secondly, All I'm suggesting is that if he is unsure of what to put in his cover letter the purpose of this thread, than the guy at the company who he spoke to initially for over and hour and multiple time after would probably be the best person to ask as opposed to random people on a message board giving generic adivce.
In short, it's asking for a clarification from a prospective employer about specifics on INFO THEY ARE REQUESTING. don't see how asking someone for clarification or ideas on what they are specifically asking for is the same as someone calling continually to check the staus of an already submitted application,
Also, something that may be lost in the whole point is that this is an INTERNSHIP, not a paid job, the majority of people taking internships are younger guys with little or no experience, so it has to almost be expected by company that some may ask for help submitting an application that covers all the specifics they may be looking for,. If the guy already had a conversation of over an hour and multiple since, I'm sure he wouldn't take issue with a quick 5 minute call asking for clarification of what specifics they are looking for.
Since I wasn't present for the conversations, I can only guess that there was a bit of a personal connection made based on number and lengths of conversation, which is why I suggested at the far end of possibilities to even see if the guy would proofread a draft, but that would be if a personal connection was made to the point it seems like the guy is wanting to help him get the position, otherwise it's just asking for a simple clarification of details they would be looking for. Again, this is for an INTERNSHIP where the average applicant is most likely not very experienced with the process, such as the OP and his advice seeking!
The OP was asking if he should mail a draft copy of his cover letter to the guy for his edits and inputs....which is a BAD idea.
Talking to the guy about the company and the position is fine.