Ok, this is basically a "I just got owned so lets post a nerf thread" post. I still think it's valid tho.
Basically infiltrators ignore force-fields, AND they do kickass damage against em. I decided to go ingame and check. 8000 per hit against force fields (and turrets) for Mark I. Their base damage is 40. That's a 200x multiplier.
So, a little math. Mark III force-field has 56,000,000 hp. Infils Mark I do 8000 damage every 1.5 seconds with a cap of 475 to them. 56,000,000 / (8000/1.5 * 475) = 19.64. Just under 20 seconds.
Heh, infiltrators are better at killing force-fields and defense then bombers are.
Why is their ability to kill force-fields a problem? Because then your home station (or w/e else is under it) becomes vulnerable to anything else on the planet, such as bombers, and recently nerfed starships.