Can someone explain the basis on which it is advised to group diverse pieces of evidence? For instance if I want to group a winning a hackathon, articles published in conference, talk given in conference, high salary, and leading a venture. What rule of thumb should I follow to place the evidences in one or different evidence documents?
I don’t think there is any rule of thumb.
It also depends on how much space you have.
If you have less space you can squeeze multiple evidence into 1 document (3 pages). If you have more space you can spread them across different documents.
Just make sure the evidences are related to the criteria and to explain the distinction from other evidence in the same document.
In my case for MC, I had multiple evidence for high salary so I combined everything in a single document.
If you have multiple evidences that are related to each other, it makes sense to put them all as a single piece of evidence. But if you have just multiple but unrelated to each other (under the same criteria), you can put them in the same evidence and explain their distinction so as not to confuse the assessor.
But it still largely depends on how much space you have and how strong the evidence is.