If you said Gear, you'd be wrong.
If you said, crowd control, class knowledge and timing you'd also be wrong.
The biggest indicator is Positioning. You can welfare your way to gear (4/5 brutal, merc shoulders and weapons), cc like a madman, read up on every class, and travelform away while intercept is down like a pro, but if youre standing in the wrong place, you're dead.
Positioning is everything in this game and a majority of the most game breaking and basic skills require line of sight (LOS) : every CC, every ranged dps spell, every heal requires LOS. So why don't more people use and abuse it?
That's a very good question.
The answer is probably because your average PvPer has a mindset of "I'm going to run up to that tower there and spam my abilities and hope that I kill them." or "I should be okay to stand behind these people and spam my heals until i'm oom." And this is probably the biggest reason why your average player gets into the arena and gets demolished or eats a cc train longer than the time spent in pre-match buffing.
Knowing how and when to LOS is all about global awareness, and this applies to everyone from melee to healers. Obtaining a level of field view takes practice, but with it, one can tell when to duck behind that corner and when to pop back out. Is that disc priest's hands glowing black? Better get out of the way of a mana burn. Mage's hands glowing white? Shuffle behind a pillar to avoid that poly.
While this is an obvious statement on awareness, much of the LOS responsibility is also between teammates. Is it really that smart to run behind that pillar when your healer is halfway across the map? Probably not. Are you chasing a target around a pillar to flush it out into the waiting arms of your teammate? Hopefully, yes. Are you standing in the middle of the map when the other team has all ranged burst dps? Hopefully not.
The point is, nearly every situation, except for a certain few, allow for LOSing. Use it to your advantage and be aware of other people using it against you.
Here's a brief list:
- The huts that contain the buffs are good for popping in and around
- Entrance archways usually have a little edge to pop behind
- The floor of upper levels can restrict LOS
- Flag stand area has little indents
- The cubby hole in the flag room is great
- Seige weapons on horde side past the GY
- Mine: Entrance to mine
- BS: Smith building and LM/Stables side ledges
- Stables: Stables building and bridge to LM
- LM: LM building
- Farm: Farm building
- MT: Around the back and the pillars to either side of the tower entrance and the little cubby inside the tower
- DR: Use the weird ruin building geometry to lose people
- BE: Around the back and inside the tower
- FR: Metal junk to the left (while facing FR) of the Fel Reaver.
- Tomb (obviously)
- Starting areas
- Indents where the sight buffs appear on the outer wall
- Giant tombstone is hard to see around
- 4 Giant pillars
- Starting cubbys
Blades Edge Arena
- 4 Posts at each end of the bridge
- Standing on the opposite side of the bridge widthwise if the opponent is casting from the ground level
- 4 giant pillars (watch out for the hunk of meat)
- Starting cubbys
Really, there's no shortage of LOS possibilities, except, perhaps the Dun Baldar bridge, so there's really no excuse not to use it to your full advantage! Of course, none of the roads between BG objectives and the EOTS flags have LOS-able terrain... but of course, we don't stop to fight there anyways, right?