They have stacking penalties .

Edit : You know why this is a thing .?. and this is just my opinion .... it's the fact that the skill set is 8 multiple to even access HAV's and now more then ever you have people skilled into AV when before the redesign you only had a selected few and even fewer that were dedicated , now that's changed . Couple that with the amount it takes to max that out to access PRO HAV's and even more to max out your vehicle skill tree , turrets , fitting for those said turrets along with damage mods and the fitting for those as well and like you said , you yourself just came into the ADV part of this journey where someone like myself has everything vehicle maxed out including the ADS of my choice , now that's about half of my SP's where the other half goes to my infantry ( I play Logi and Commando ) the weapons that I might have maxed and my infantry core which isn't totally maxed , including my weapons fittings as well since I have SP's in that because I focus on anti-vehicle so that's suits , core and weapons .

It's a lot and a lot should take down a PRO tank but you have many that disagree but you can't disagree with the amount of effort and time that it takes to be a vehicle specialist , that can't be denied and I believe that CCP is just trying to put that hard work to good use , now are there problems .?. sure but like many that plague this game it's taking and will take some time to figure those out but the answer ( if you look and read the post ) is not to nerf certain AV weapons like the swarms and if you are having trouble then that is clear evidence that swarms , just like every other AV weapon need to be at it's best to deal with these threats .

In short I just believe that things are the way that they are because it takes so much time and effort to be a vehicle specialist and to have someone just come in and 4 to 5 shot you is just silly unless their in a HAV and that's another thing that I believe that CCP is trying to do is make vehicle v.s. vehicle battles a thing now so that these same people can enjoy their investment , not be easily ganked , and have a dynamic that's like no other and one that's worth while as well for the enjoyment of those who choose this role .

A little time , effort and patience is involved but the answer is not always to nerf something but to bring the counters up to speck to add another dynamic to this role .

Most are just so shortsighted and not thinking about answers or true solutions that would help make all involved not feel slighted , I read everything that has to do with vehicles and anti-vehicle and it is truly a $h!t ton of bias involved from the community in both respects .

Sorry for the long post but it's what I do . Not that .. that makes it right but this like the game is complex and shouldn't be taken lightly or delicately .

You really think that you should kill full pro tank with that fitt? ?

How much sp you got into tanks?