No. As I said, upthread: "First, you'd need to characterize the drive -- how much skew is there between backplane drive and segment on/off drives (any skew will appear as potential glitches on a static, combinatorial logic decoder so you would have to *sample* the decoded outputs at some epsilon after each BP clock edge)." You have no guarantee that the phase of the backplane has any fixed relationship to the phase of the segment drive signals. It could precede them -- or follow them -- or both (precede some, yet follow others) -- or vary (temperature, value being displayed, etc.)
Per OP: "off-the-shelf commercial unit where the LCD display is driven *off* a uC" (also note that the OP conditions the request with "not pic/Pi/uC" to capture the display data)
[If you've got an MCU lying around, let it watch ALL segments and trigger/sample BP drive from which it can derive an appropriate segment sample time appropriately SKEWED from the BP to ensure the segments are stable at their INTENDED levels]Nonmultiplexed displays have a great deal of tolerance as to what is required to "illuminate" segments. As the outputs from the "driver" (which is probably a programmed MCU and/or LSI) are expecting to "see" an LCD, there, its unlikely that you will find a formal specification (timing diagram) that indicates a fixed, causal relationship between BP signal and segment drives.
OTOH, any *logic* that you have hanging on those signals will be very intolerant of phase differences between what you *thought* (when the circuit was implemented) and what is actually happening
*now*.