I progged through the first two phases within a few hours of release in PF and came to understand most of its mechanics for those phases. So that far is at least possible without looking up guides and so on.

The tile phase is really where you're all relying on eachother and may need raid planners. You don't need a second monitor for that, because you can just tab out, and soon they are adding a raid planner into the game.

Discord isn't normally, actually required. It usually just allows someone to do callouts to make it easier for you, or the direct communication between players can reduce the amount of wipes a bit. I have already seen a number of people say how they cleared via PF in my social circles.

Being flawless with damage also doesn't matter. People have cleared with lots of damage downs, and it's not scaled for 730; it's scaled for 710 (crafted gear) despite that most players doing it probably have 720 or higher.

I think whether it's 1% is subjective. According to Lucky Bancho's latest stats, many JP worlds have 30% of (post-Dawntrail players) who cleared savage, while Aether has around 15% (varies 14-20%).

If we get the number of people with the M4S mount and contrast it with the number of people with the M4 minion (based on data from collectors), it gives us some sort of vague estimate of the number of people who have cleared savage: 24.7%
If you do finally fill up three teams, it is only a matter of time before one person leaves and the alliance goes from 24 to 7.
That is a bit annoying. Would be convenient if we could recruit more without leaving the instance, because we have to get 24 people to leave then re-enter each time it happens.