I suppose the value of the intel would vary on a case by case basis.
It is well know that the slave society had a very effective grapevine. News and information tended to travel very fast.
I would agree with you on that. The CW was a very interesting time militarily speaking, with both elements of large scale planned out contential style battles mixed with numerous quick skirmishes and guerrilla tactics on both sides. Depending on the battle type the info maybe useful or too old to matter.
There are a couple of good books on the Union use of the Telegraph BTW. They laid out something like 10-15K miles of lines just for military use, first time in history electronic communication was set up strictly for military use.