First of all, I concur than this sort of splicing is easier in B&W than color, where untreated differences in color temperature can lend a false note. But, take comfort (?) in the following observation. In the Age of Photoshop any unusual feature of light, fortuitious coincidence, luck of timing, etc. will be assumed by an ever-growing segment of one's audience to be the result of manipulation, even if it's not. We've seen this resistance-to-believe-in-the-reality-of-the-unusual on this forum in comments on some of Michael's photos. So, relax, you are already guilty before you unpack your camera.