I learned from this that my "Guiding" planet Mercury, which is retrograde natally, is "Promethian - Retrograde". More things to learn!
My new theory regarding retrograde planets is that the retrograde motion represents lack of some sort that would cause one to focus on addressing that lack in a dramatic way. For instance, in Lapis's case, retrograde Mercury could give one a sense of a lack of information - so much so that one might demand that information from whatever sources are available - traditional or non-traditional such as in a psychic manner.
Given the position is in Sag and very close to the MC could cast this into a spiritualist role of psychic reader.
I personally have Uranus retrograde in Leo in the 6th house which is expressed as an early feeling of a lack of freedom to my myself in the workplace. This is still going on but I've made great strides in creating a freer workplace for myself in that I've been able to work from home 10 of the last 11 years.
I also have Pluto retrograde in Virgo in the 7th house which would account for a feeling of powerlessness in relationships especially in dealing with the drier Virgo aspects one would expect: being prim and proper, clean, detailed, restricted.yada yada yada. This has played itself out by me learning how to own my own power without taking someone else's and getting more comfortable in my own skin.
Back to topic, I have Saturn as my oriental planet - direct conjunct the MC in Sag which encourages me to become some kind of spiritual authority or a good lawyer (which I might need if I abuse the power of the former).
I find it interesting to see how these planetary anomalies - oriental, retrograde and others continue to deepen one's picture of the subject at hand.