This isn’t a fact. This is your opinion. The 1st phase of a pit is going form the start to the portal. If a player is overkilling the creeps (ie 1 shotting them), the other players can just walk behind that player offering no benefit from getting from point A to point B. Now we’re left w/2 phases.
The 2nd phase would be the most beneficial to multiple players, but only if they all fan out in different directions and the map is made in a manner that this is doable. There are maps w/fewer fork points than others.
The Boss again depends on the Pit lvl, if you’re wiping it quick w/o a group then having a group won’t speed things up that much. As a mentioned before have a minimum drop rate until about tier 90 for people who want to group while the get mats, then after diminishing returns and it’s about challenge/bragging rights and not the resource grinding.
Seriously, if a person can solo a run in 5 minutes, then what’s it matter if a group does it in 3 or so minutes when using your #s? You’re leaving out the dead time it takes different members to sort through/sell gear, masterwork an item, bio break, smoke break, other rl stuff that comes up in between runs which can easily go over 2 minutes time.
Tbh, there was much more variance between previous season NM runs (which were their end games for finishing glyphs) than this.