I would start by seeing if the Graphic Processor is turned off rectifies the problem.
It can cause problems along the lines you have described.
Yes, will try running with the GP off. Ugh...
I suppose, however, if I have to trade off a bit of speed in order not to see the image go momentarily black, I'd probably leave things as they are and live with the problem. Frustrating, isn't it?
But thank you for your reply!
Indeed, using the GPU is causing the problem.
Who, then, is responsible for fixing it: Adobe or Apple?
I'm curious if you are seeing a performance hit with the graphics processor disabled in Lightroom. The graphics processor is primarily for those who have high-resolution (4K monitors). You really shouldn't notice a difference if you don't have one of those monitors.
Indeed, using the GPU is causing the problem. Who, then, is responsible for fixing it: Adobe or Apple?
From the outside, it's hard to know the root cause. It could be a bug in the graphics driver (from Nvidia or AMD), in OS X, or in LR. Sometimes there's quite a bit of internal finger-pointing amongst engineers. But precisely because it's outside of customers' control and understanding, it's in Adobe's interest to get the issue resolved by working with Apple if necessary.
Your symptoms sound similar to this bug report in the official Adobe feedback forum: Lightroom CC: Image "blinks" when toggling between "Before Only" and "After Only" views in Develop module | Photoshop Fa… . I suggest you add your symptoms and the output of Help > System Info.
At least with my 2016 13" MBP, yes, there absolutely is a performance hit when the GPU acceleration is disabled.
Simple operations such as zooming and panning are noticeably degraded when GPU is off. Rather than a smooth move, it's a series of stutters.
Try it out for yourself; you will see the differenced in performance on the MBP's display.
I just (yesterday) bought this upgrade specifically to run on this machine… and that's because Lightroom 5.7 was slower on this than my 2010 MBP. Am extremely frustrated and disapointed.
Would love to get my money back. Point me in the right direction.
Thanks, Johnrellis. Will follow your advice and the link.