I've experienced it working well-enough in groups of 3-4, depending on everyone having decent internet at that time and on the software used. Just like regular mobbing IMO there's some circumstances where it'll feel like the right method, if it's a method you've occasionally practiced.

Here's some free marketing, I am not affiliated with any of these co.s: The best tool I've used for multiple users was CoScreen, because it shows everyone's cursors and allows simultaneous sharing of windows from multiple coworkers. So per that point in the OP that the major benefit is "trivia" knowledge, if you have one coworker who can quickly solve subproblem X from their terminal, and another who can quickly solve subproblem Y from their terminal, both terminals can be shared simultaneously and everyone can gain that context.