Sharla
When I was learning astrology in the 1970s from the gurus of "psychological astrology," retrogradation meant an internalization of the planetary energy, such that it wouldn't manifest clearly in the realm of outward affairs. Interception had a similar connotation, if I recall. It seems that combustion can do something similar in traditional astrology, in that the Sun "washes out" the planetary influence.
Hmmm well this mercury rx in my chart, has had enough of an effect on me. Its like i have all this stuff in my head but when i try and speak it, it comes out in all a mumble jumble.
Infact i even struggled at college because of this, my tutor even thought i had dyslexia and told me to take a test for it....but i knew it wasn't this and could never figure out what was wrong with me, i always used to sense it was just some sort of mental block....well at least now i know what it is.
I doubt id ever be able to do face to face readings because of this either, im much better at typing something out.
I find it hard to explain myself at times, and i can get tongue tied, i can also feel like people think i'm stupid and childish when i speak to them....this as you guessed then makes me just not speak at times, so then i'm perceived as either being rude or shy, i can't win.
So in regards to internalization of the planetary energy and not manifesting clearly outwardly, then yes very much so.