@Baron:
The Triple A 1942.2 SBR rule is each plane get Att or Def @1 and StB get 1D6 damage.
However, the math also shows that it is not better to bring along Fg as escort than throwing only StBs.
Almost the same odds: 0.825 IPC/ SBR run (with 1 StB 1 Fg) vs 0.861 IPC/ SBR run (with 2 StBs).
The only difference is with 2 Bombers there is much risk (of loosing more IPCs) but also much reward (more damage against the defender).
From this, my analysis will be that there is no need to escort 2 bombers or more with Fighters as long as you get a 1:1 ratio against defending interceptors. Better to put your Fgs on other missions.
Below there is the maths.
Triple A SBR 1942.2: 2 StBs A1 doing SBR against 2 intercepting Fgs D1
Sum: +8.195 - 7.334 = + 0.861 IPCs damage/StB
I can also add that it is even more the case with G40 SBR, no need to throw a Fg on an escort mission if you have at least 2 StBs and a 1:1 ratio against defending interceptors.
According to the maths of G40 OOB SBR rules, the odds to inflict damage to the defender are clearly increasing keeping 1:1 ratio, from 1 StB, 1 StB+1Fg and, finally 2 StBs.
The odds are even better than a single bomber against an undefended Industrial Complex ! ( +2.583 vs + 3.639 IPCs damage/SBR run)
G1940 SBR: 1 StB doing SBR without interceptor/ damage 1D6+2
Sum: +4.583 - 2 = +2.583 IPCs damage/SBR run
G40: 1 StB A1 doing SBR against 1 Fg D1 / damage 1D6+2
Sum: + 4.845 - 3.666 = + 1.179 IPC. damage/SBR run
G40: 1 StB A1 doing SBR against 2 intercepting Fgs D1
Sum: + 4.85 - 5.056 = - 0.206 IPCs damage/SBR run
G40: 1 StB & 1 Fg A1 doing SBR against 2 intercepting Fgs D1 damage: 1D6+2
Sum: +7.775 - 5.33 = + 2.445 IPCs damage/SBR run
G40: 2 StBs A1 doing SBR against 2 intercepting Fgs D1 damage: 1D6+2/StB
Sum: +10.973 - 7.334 = + 3.639 IPCs damage/SBR run
G40: 1 StB & 1 Fg A1 doing SBR against 1 intercepting Fgs D1
Sum: + 7.639 - 3.667 = + 3.972 IPCs damage/SBR run
G40: 2 StBs A1 doing SBR against 1 intercepting Fgs D1
Sum: +11.459 - 5.666 = + 5.793 IPCs damage/SBR run
Triple A SBR 1942.2: 1 StB doing SBR without interceptor (A1 vs D1, damage 1D6)
Sum: +2.917 - 2 = +0.917 IPC damage/SBR run
Triple A SBR 1942.2: 1 StB A1 vs 1 Fg D1
Sum: +3.69 - 3.667 = + 0.023 IPC damage/SBR run
Triple A SBR 1942.2 : 1 StB A1 doing SBR against 2 intercepting Fgs D1 / damage 1D6
Sum: + 2.025 - 5.056 = - 3.031 IPCs damage/SBR run
Triple A SBR 1942.2: 1 StB & 1 Fg A1 doing SBR against 2 intercepting Fgs D1
Sum: +6.155 - 5.33 = + 0.825 IPC damage/SBR run
Triple A SBR 1942.2: 2 StBs A1 doing SBR against 2 intercepting Fgs D1
Sum: +8.195 - 7.334 = + 0.861 IPC damage/SBR run
Triple A SBR 1942.2: 1 StB & 1 Fg A1 doing SBR against 1 intercepting Fg D1
Sum: + 5.973 - 3.667 = + 2.306 IPCs damage/SBR run
Triple A SBR 1942.2: 2 StBs A1 doing SBR against 1 intercepting Fg D1
Sum: +8.403 - 5.666 = + 2.737 IPCs damage/StB
OOB SBR rules for 1942.2: 1 StB doing SBR without interceptor damage: 1D6
Sum: + 2.917 - 2 = +.917 IPC damage/SBR run
OOB 1942.2: 1 StB A1 first strike vs 1 Fg D2
Sum: + 3.8 - 4.8 = - 1 IPC damage/SBR run
OOB 1942.2: 1 StB A1 first strike doing SBR against 2 intercepting Fgs D2 / damage 1D6
Sum: + 3.071 - 7.185 = - 4.114 IPC. damage/SBR
OOB 1942.2: 1 StB & 1 Fg A1 first strike doing SBR against 2 intercepting Fgs D2
Sum: + 6.018 - 7.555 = - 1.537 IPCs damage/SBR run
OOB 1942.2: 2 StBs A1 first strike doing SBR against 2 intercepting Fgs D2
Sum: +7.547 - 9.556 = - 2.009 IPCs damage/SBR run
OOB 1942.2: 1 StB & 1 Fg A1 first strike doing SBR against 1 intercepting Fg D2
Sum: + 5.973 - 5.159 = + 0.814 IPCs damage/SBR run
OOB 1942.2: 2 StBs A1 first strike doing SBR against 1 intercepting Fg D2
Sum: + 8.214 - 6.315 = + 1.899 IPCs damage/SBR run
So the only case for advocating Fg escort is within OOB SBR rules from 1942.2, the odds are less worse for the attacker if it keeps pairing 1 StB with 1 Fg.
Playing 1942.2 online with Triple A SBR rules however, it is a different story. As in G40, 2 StBs has almost the same odds of doing damage as a single StB raid against an undefended IC.
(.861 vs .917 IPC/SBR run)
So, based on these comparative stats, we can say that the actual OOB 1942.2 SBR rules is more historical than the 2 others, since the game mechanics give less risks for bombers when paired to Fg but it is at the expense of making SBR strategies much less appealing for attacker, and for Allies in particular.
Here is the link to HR forum for what I think is a more historical and balance SBR rules:
http://www.axisandallies.org/forums/index.php?topic=34118.msg1311386#msg1311386