I myself have joined PF Parties that were farm parties with out the clear.

As a general rule though, I do either tell message the party leader for their approval or join the party and immediately inform them of my "noob" status for the general consensus of the team.

If they're not ok with it, I politely bow out. (How ever, being rude and just kicking with out saying anything after I've been honest will almost certainly result in being placed on my black list)

I've been given a chance before with out the clear and the team just ask me politely to leave until I have some more experience, and I politely thank them for the chance and bow out. I've also been given the benefit of the doubt and completely wreaked the boss with the party like I had run it a hundred times. (Which I usually have via trying and dying).

How ever, the rudeness of not speaking up prior to a run and ending up ruining it for every one else is something that needs to be culled as it make for an even more toxic environment. And the Elitists are already toxic enough with out being rilled up by inconsiderate trolls and rude "Sleeper" rookies sneaking in to the elitist farms.

I guarantee there'd be more nice "Farm Masters" willing to give people a shot if people would stop being rude and jumping in Farm parties with Zero experience. (And I'll personally attest that a video is no substitute for practical experience in raid level content)