I regularly run a "poptard" TBT-5J, one of the major weaknesses of the poptart tactic is positioning (the majority of the time your shooting once or twice from same spot) - outmaneuver them by getting your team to flank or just wait till they pop in the same spot and light up their CT.
Many matches I finish with only 285 or so dmg (not because I suck) but because the poptart thing scares teams into choke points or into the gaping maw of the enemy team, and then is killed shortly thereafter.
To combat poptarts do the following:
1.) Stay Calm
2.) Communicate with Team
3A.) Group Aim Them
or
3B.) Outflank and close range (this is especially true for the stalker boats which use PPC for heat and the smaller pops like the TBT5J
edit
3C.) Find cover - pop tarts can only hit you in certain areas so move to a spot with more cover and make them come to you.
If your team sucks then there never was any hope whether it was poptarts, ecm imbalance, ravens, (insert something thats high powered here)
Oh and all I do is PUG so its not a organized play thing (though that does make any advantage much stronger)
Edited by Bobdolemite, 16 April 2013 - 04:04 PM.