These last couple days I've been playing with weapons balance in response to the new AM cannon rules. Whoah baby, have I learned a trick or two. I used to think big gun=more boom= better. Nope. If you put 100 Pont's of damage on a block it breaks. If you put 1000 points on it... It still just breaks and none of the damage is transferred to neighboring blocks. My test platform has been a refitted TOS Miranda. I am removing her big AM arrays and replacing them with a bunch of smaller arrays each tuned as closely as possible to remove a single block with every impact. The arrays in each meta-array are lined up longitudinally so the shots follow as much as possible the same trajectory. Good grief, its a flipping buzz saw. I can rip through my ballistics gel at least 3 times faster than my previous configuration. And not once have I hit an energy deficit.
No, AM cannons have not been Nerfed to uselessness as far as I can tell. Try using AM Cannons arrays of about 125 blocks each. More and you are wasting energy at impact. Less and you are wasting energy at firing point.
The new version of the Miranda TOS will be out soon. Seriously, I'm going to have to rebuild the weapons on all my ships.
Good Hunting!