This is awesome stuff! But it's a little frustrating, too. I just published a book on Col. Hoyt (no relation) via Kindle and in the epilogue I try to clear up the controversy over whether Todd was killed in battle as John N. Edwards (Noted Guerrillas) claims, or whether he was killed the day after Second Independence while on a scout, as Connelley (Quantrill and the Border Wars) claims. Based on a couple of primary (Union) sources, I conclude that Todd was killed by Hoyt, probably within Independence itself, on the first day of the battle. But it would have been really, really cool to demonstrate that Hoyt and Todd were mano-a-mano as Price and Shelby were pushing the Union troops through Independence on that first day.
So how do all you other authors handle this? When valuable information arises too late to be of use to you, do you just cry in your beer? Or do you just vow to press on?