From 'The Image says: The good fortune of persevering in rectitude' to 'Not a robber, but a marriage alliance.' The Proper Meaning states: 'Graceful yet white and plain'—po denotes a plain white hue.
Six in the Fourth Place has its resonance in the initial line and wishes to go and follow it, but the third acts as its obstacle, causing hesitation. At times it seeks cultural refinement, hence 'graceful'; at times it preserves plain simplicity, hence 'white and plain.'
'A white horse, winged and swift'—it merely keeps its horse clean and bright, its coat gleaming like wings, hesitating and waiting, not daring to advance abruptly.
'Not a robber, but a marriage alliance' means that were it not for Nine in the Third Place acting as an adversary, it could immediately conclude a marriage union with the first.
The Proper Meaning states: 'Six in the Fourth Place is in a position of doubt'—because it is in its proper position, it should resonate with the initial line, but being impeded by the third, it falls into hesitation.
If it were not in its proper position, it would not resonate with the first, so why would it hesitate over wanting to go?
'Not a robber, but a marriage alliance, in the end there is no blame' explains the meaning: if one waits until there is no threat from robbers before concluding the marriage alliance, there will ultimately be no fault or error.
But if one braves the hazard of robbers to pursue the marriage, there will surely be blame in the end.