I will stalwartly continue to provide unfounded opinions, poorly researched claims and barely logical arguments. Feedback is welcome - just see if I care! 
1) I believe "Friday's Child" already ignored the Organian peace treaty and implied that a mishandling of the Capellan problem could ignite a Fed-Klingon war. Thus, perhaps whatever happened to the Organians had already happened at this point, and war was again considered so imminent that convoying of freighters was necessary.
It might be that the Organians never enforced their treaty after the two intruding races had signed it, and only the political convenience of the treaty kept the Feds and the Klingons respecting it as long as they did.
An alternate explanation is that there were other conflicts going on, against other races. There isn't any canonical hint of such conflicts, unless it's the Tholians raising their ugly multifaceted heads (helmets?) again. They could well reside near the Klingons, as per some TNG references.
2) Nichols probably just swallowed a comma: the script probably read "..another distress call, from USS Carolina". One could of course also argue that no distress calls are acknowledged unless they are repeated, but that doesn't sound like the Starfleet we've learned to know and love. The only Fleeter so far to have ignored a distress call the first time around was Pike, and he had good reasons to do so.
Perhaps the Klingons goofed up and made the distress of the Carolina sound too severe the first time around, something that would have killed all the crew for sure before the Enterprise arrived. Then Scotty would automatically have abandoned any attempt to help the ship even if he thought the call was genuine - going to help survivors could be an all-overriding priority, but going to survey a dead wreckage would not be.
Timo Saloniemi
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