It's the guild's first experience. You will fail many times before you succeed. If you expected to get a full clear on your first try with 20+ strangers, be realistic. Especially if you are a casual raid guild that raids once a week. I've been in a couple of those and did that once myself. Guess what happened? Same thing. Don't be afraid to fail to the point where you need to create standards for entry.
Seems it would be better to get prospective raiders together and complete challenge dungeons or even lower teir raids/flex raid. There is more variety to what may happen and they will need to work with a group. There is little or no need to have chemistry with a group of others in proving grounds but getting some together in dungeons/raid will better gauge their response when working with others.
The first time anyone in a guild "required" me to do anything I deemed unnecessary, I'd be gone before they could even complain I wasn't listening.
I would probably raise an eyebrow if my guild suddenly requests something like that, because we already are a raidgroup with members who should trust each other. But if your forming a new raid group at entry level (like stated in the first post) its better way than any "post a ui screenshot", "what's your ilvl", "post a lfr log" criteria.
i remember reading an anecdote about when damage meters were first introduced. there were 3 mages in the raid, two of them constantly belittling another one because he wasnt 'as good as they were'. once damage meters were used to track the raid, it became clear that the situation was the opposite, and they quickly shut their mouths.
This seems like a great idea, back when Brawlers guild came out. I felt that even that could be used as a great tool to judge new raiders, taking somebody who has beaten brawlers guild and gotten gold on proving grounds would make a much better recruit than somebody who didn't or can't.
Not even doing Proving Grounds, yet i'm raiding.
Evect - Chamber of Aspects - Elemental/Restoration Shaman Shaman - changed jobs and i'm back in the game!
I think proving grounds is valuable to train and demonstrating understanding of SOME raiding concepts, but I don't think it is really important. The most important skill that 90% of the group can have is being able to follow instructions, and proving grounds does not teach that.
In B4 the bleeding hearts at Blizz say "O Noes! Guilds using PG not for what is is intended for??? We better nerf it asap so people aren't sat for raids!"