I have 3 questions related to this:

- Can multiple players of the same team fight their own team gym in order to raise its prestige? 
- If you have any experience with this, then can you also include the amount of Prestige you gained for your gym and the CP of your attacking Pokemon versus the defending Pokemon in the gym.
- What would you recommend, fighting your own team gym alone to raise it's Prestige or fight with a group (if it's possible)?

Before someone marks this as duplicate, I want to mention the question was asked as part of this one, but not answered: https://gaming.stackexchange.com/questions/274445/battling-at-a-gym-simultaneously-with-other-players