I have yet to find a reasonable explanation anywhere as to what TMPGEnc VBR P or B picture spoilage really means. I would infer that spoilage infers something like ruining quality. My guesses for spoilage are: 1) reduce the motion search precision for the macroblocks in the frame, and/or 2) reduce the quantization bits in the frame's macroblocks. What is most bizarre about spoilage is that its setting range is -100 to 100, which I would infer that a negative setting "improves" quality. I've experimented a bit, it seems that lower values improves quality and increases size. I've yet to try a negative value.

Does any REALLY know what this setting does in a technical sense? Or is this stuff simply a dark art and that I should leave well enough alone and agree that "this setting usually does not need to be changed".