According to wiki
You can pre-plan out for a lot of the raid like how many DPS do you need and healers and support; where the key position and all that kind of stuff
https://ashesofcreation.wiki/Raids
So if players will know this, then of course they will not take 6 tanks if only 5 are needed, isn't it?
But then is this true for all kind of tanks?
Why do we have 64 classes?
Is the secondary archetype important?
Will players ignore certain classes in dungeons and raids, like Guardian-Bard and Guardian-Rogue?
If in future they'll want to add one more class, that means we get automatically 17, to keep the matrix representation?