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*huh*? Okay, I've never used the "Blockade Box Handling" option, but I think that affects .... wait for it ...
wait for it ... the
Blockade Box only and not the
Shipping Box; but I might be wrong.
What I can say is that I have never, ever,
ever sent a ship out of the Shipping Box because it was low on supply, not even patrols like the African Squadron; only when they've lost enough cohesion from fighting and storms.
How you handle your trading fleet(s) in the Shipping Box depends on what the South is doing. If they are not building and sending a lot of raiders into the Shipping Box, you can leave all of your transports and merchantmen in one big fleet-stack without a worry. Just keep an eye on the message under the "Key Messages" that tells you how much money and WSU you are getting each turn from shipping. It also tells you how many raiders have been spotted.
If you see that number going up, see that there is a stack in the Shipping Box with more than a couple of ships in it or start having your shipping fleet attacked --you'll get a report in the battle messages and see bombardment during the turn execution-- then you might want to change your strategy.
Ideally you would want to break your shipping fleet into numerous smaller fleets, each escorted by a frigate squadron. The frigates have the best spotting characteristic and will help your fleets avoid being caught.
Parallel to that you can also take also take a more aggressive approach and send hunter fleets combined of frigates and steam frigates into the Shipping Box; about 2 - 4 of each; having a naval leader can also help.
Send them constantly in and out of the SB. It seems to greatly increase the chance that you will find a raider. Why, I don't know, but it's been my experience.
It is not likely that you will actually sink a raider --I can't remember ever having sunk one in the SB--, but if you catch them you will generally score a lot more hits than they will, which will lower their cohesion, lessen their effectiveness in raiding[SUP]2)[/SUP] and send them back to port that much more quickly.
The biggest issue you will have is where to take all the patrol-ships. It takes 240 day to build a frigate or steam frigate and they're not cheap. You can take them out of the Atlantic Fleet, as long as you are not using it for anything else, like patrolling for ships heading to and from ports --if you catch such, here there
is a good chance of sinking them--, or escorting an invasion. But if the CS is investing heavily in raiders, the only thing you can do is also invest.
Also, if Foreign Intervention is getting critical --like over +50-- I would start building up my fleets. France and especially Great Britain have large and powerful fleets that will rape your shipping and totally dominate the seas. Without shipping, no supplies will get transported by sea to coastal forts and harbors that might need to get it from naval shipping and the affects could be devastating, depending on the situation.
1) That's me reading to myself
2) The more effective a raider is, the less money and WSU you will get each turn from shipping.