Just as other ships may, submarines may also move out of a sea zone where they begin their turn with enemy ships, even destroyers. The destroyer doesn’t stop the sub’s movement, as the sub didn’t enter the sea zone - it started off there.
Put that in the FAQ
If you play with tech, radar and increased factory production can both strongly discourage SBR.
I have never been in a game of who can roll the most ones since classic, with 3 dice heavies. I play a variety of opponents and rarely get SBR’d. And it’s not because I have techs or interceptors on.
Like axis said, sometimes you get sick of these kinds of games (I can imagine), but since I’ve never had an opponent bomb me much, I look forward to the day that someone does.
In AA50 I’ve never seen someone use SBR as an attacking strategy. Many players don’t do anything at all with their bombers some turns, when they could be SBR’g. I even played someone who had heavy bombers from round 1 with Germany, and some turns let 3-4 heavies sit there idle while UK remained untouched (yes, this mystified me). But people don’t want to lose their bombers to AA fire. SBR is very risky. You can take in 2 bombers, and it seems like I usually lose 1, so I’ve lost 12, and the recipient loses 1d6. Now I know that’s not the way to run an SBR campaign or anything, but I’m just saying why a lot of folks won’t bother, if there’s an AA gun. Besides, the cap on damage limits efficiency in many cases (reduces average below 3.5 per surviving bomber) and you don’t bomb money directly anymore, so the victim does have some options many times.
What I’m trying to say is, I’ve only seen SBR when people don’t know what else to do with their bombers for a turn, or there is no defense (no AA gun). Bombers are extremely useful in attacking military units, and that’s the way I and most of my opponents use them.
Even if those extra Fighters survive the battle and then have to crash into the sea?
The thing is, you don’t know if those fighters will have to crash into the sea. They may end up on non-combat move without a valid landing spot but when you perform your combat moves there’s always a statistical change that the carrier will kill the 100 battleships (even though it should be about the same as you de-materializing while reading this message and materializing on the next room) thus the combat move satisfies the rule of a valid landing spot (regardless of how improbable it might be).
Combat moving 2 extra fighters to a battle goes against that same rule because there’s simply no possibility for those fighters to land during non-combat as they are moved (unless a carrier magically pops up out of nowhere into the middle of the battle board - odds for that happening should be the same as you teleporting yourself to another room) .