Chops its been asked again and I am certain that we have had this discussion so I just wanted to see if you recall where it went or what plans you have to implement anything to support it.
The discussion was an old one that centered around the applications really just creating a thread and not relating to the anything that the applicant can come back and see once it is submitted. My guild would like a means to be able to pose followup questions to an applicant via the process. Maybe they didn't answer a question clearly and rather than just reject them or look for them in game they would like to be able to pose the question back and have them provide an answer to the new question. Obviously this creates a couple of problems. 1) the application process itself needs to create an account (preferably with the name they supply on the application) to allow them access back to the forum thread for their application. 2) there would need to be a way to have the reviewing members of guild post comments in the thread that the applicant couldn't see. This would almost require that 2 threads get created. 1 for the correspondence to the applicant and one for internal use only. Complicated eh. I'm just relaying back what was asked of me.
I did like the idea of a polling mechanism to be created when the application was created. I think this could solve some issues.
What if application posts had 2 reply buttons.
Reply - Private
Reply - Applicant
Where the applicant is excluded from the former.
I know that's further complicating your security and private threads by taking it one step further and putting permissions on a per post in a thread basis, but this could be just for the application threads.
I would not reccommend this feature be allowed on general threads.