think it also applies to attacking subs. They can retreat in any round by submerging INDEPENDENT of what any other attacking units are doing. The language cited above (LHTR Rules) grants them the ability to submerge during step 7 - it does not mandate that all other units must retreat at the same time as them.
Yes, that is true. I never said all units have to retreat. I simply think that subs have a special way of retreating on their own, just like air units can retreat from an amphibious assault. I think there is no reason to give subs a separate, preemptive retreat before other units. Subs indeed do have an INDEPENDENT way of retreating, just like air units in an amphibious assault have an INDEPENDENT way of retreating, but it still goes in the retreat step. I see no reason to give subs the option to submerge FIRST. It is an independent WAY of retreating, but it is not a separate step. If you retreat, you retreat. There's no preemptive about it. You either go downwards or backwards immediately based on the commander's decision. You don't wait for the defender to retreat, that's just silly.
1. Attackers get to retreat. They can do some combination of submerging subs, or running all normal naval units and some subs away, whatever. Submerging, like you pointed out, is NOT some special in-combat move. It is just like retreating. The attacker clearly should get the chance to retreat first, since he is always given precedent with equal opportunities.
2. Defenders get to retreat by submerging.
I still completely fail to see why you want to give defending subs a chance to retreat before all attackers to retreat. It makes zero sense. There is no mandate that gives subs a preemptive retreat. How can you preemptively retreat and therefore force an amphibious assault to continue? Again, to me retreating is an instantaenous decision made by the attacker after a round of firing. He should not be forced to wait for enemy subs to submerge, and even more grossly wrong is that if they do submerge then he is forced to continue battle. Retreat should always be given to the attacker to decide provided he has any units left after a round of combat. It is not for the defender to decide to run away first, and thereby force the attacker to continue. This is completely unfounded in any sort of combat wording.
I completely agree with you that it may be the intent for subs to be only able to retreat by submerging. That is an entirely different point, but in any case, it is just that - a retreat. It is not a preemptive retreat that influences the decision of other units to retreat. Opening fire makes sense, but not opening retreat.
And I definitely think there is something that needs to be fixed with the wording. It is just very unclear per the rules out of the box when subs retreat during the press attack/retreat phase, and what it means for subs on both sides to retreat at the 'same time.' I still however, strongly believe that you're trying to create a separate, preemptive retreat step for subs that I can find no basis for. You can argue as much as you want that subs are supposed to be able to only retreat by submerging, but I don't see how you can argue that defending subs can somehow retreat before the attackers retreat.
Maybe the best way to view the whole mess is that the "base" rule is that all attacking sea units can retreat on the surface. The ability of subs from BOTH sides to submerge is an additional power granted to subs only.
This additional power of submerging can be repressed by the presence of destroyers, but destroyers cannot affect the base ability for attacking sea units to retreat to an adjacent seazone.
Yeah, that's precisely how I look at it. I don't see the connection between this and subs retreating before other units. Just because it's an additional power doesn't necessarily mean it gets to go first or something. It is just a different way to retreat, not a preemptive mode of retreat. Instead of running away laterally, you dive. Diving down doesn't somehow go before the decision for other units to run away, nor does it somehow force an amphibious assault to continue against the attacker's will.