In WoW ALL AoE abilities which not require to channel or has no cast time such as Rain of Fire for Warlocks and Death and Decay for Death Knights NOT BREAKING A CAPPING OF THE NODE.
So why in SWTOR abilities such as Incendiary Grenade, which is INSTANT CAST ABILITY, INTERRUPTS CAPPING FOR 18 seconds AND THEN CAN BE JUST USED AGAIN. So as long Gunslinger is alive this thing will just AUTOMATICLY DEFEND THE NODE WITHOUT PLAYER's ATTENTION, for exemple a door on the Voidstar!
This ability must be redesigned to not break capping. All other AoE's should be channeled, has a cast time, or just instant single blow which still reaqure player to ACTUALLY THINK to use them when he see that several people capping.
Incendiary Grenade should've be gone from interrupting a capping just like DoTs. It IS actually a DoT, it applies not to target but to the ground.
I know, my English is terrible, but I think you got the idea, Bioware.