I am coming in quite late on this thread, no time to get a look at my computer at all today until now!
I do not so much agree with the overcompensation part, but do very much agree with finding the missing element in other people. I have a very good example, my own daughter whom I have observed now for 37 years.
She has no waterplanets, nor waterhouses with planets in them, so really absolutely nothing in water. No strong angular planets except Sun in Aries in 10 and Uranus conjunct cusp 4.
Almost everything is in Air (Moon, Mars, Venus, Saturn, NNode, Uranus and Pluto) and also in houses 11 and 3!! It could not be more Airy!!
Asc., Sun and Mercury in Aries, Neptune in Sag.
AND only one planet in Earth!! Jupiter in Capricorn, and only the Sun in an Earth house (10). So she lacks Earth as well.
She does not overcompensate Water at all by looking for other ways of expressing her emotions. Her emotions are her BIG problem in life. She cannot control them and often just looses it, emotionally, and the proverbial turning a fly into an elephant is typical of her. Emotional outbursts can get out of proportion. I dont call this overcompensation, I call it over-exageration. She exagerates everything related to emotional situations and especially in relationships with men, this is causing her a lot of problems. She just feels totally insecure and not in control of the circumstances and then uses her fire and Air elements to cover this insecurity up and risks coming on too strong. She can talks anyone under the table and is a very powerful and intelligent speaker (Pluto-Mercury opposition in houses 3-9). This then scares men no end and of course she ends up being disappointed and very lonely.
Strangely enough she does not find Water friends to compensate for this lack. She does not seem to want to be confronted with emotional people and it easily upsets her when she feels the emotional expression of others.
Now for the lack of Earth. This is interesting. She has NorthNode in Capricorn in Grand Trine with Saturn and Pluto. She is fiercely loyal (Asc. Leo) in relationships with friends and almost all her friends are Capricorns (mostly women) or Virgo (mostly men). Some are Taurus, and she always turns to me (Taurus) when she needs "grounding making her see that things are not as they appear to her.
The one's that are Gemini, she gets along with very well but often end into conflict.
I have noticed that now that progressed Sun has reached her Saturn and progr. Ascendant is in Virgo, progr. Mercury in Taurus (in 10) and Pr.Venus and Mars in Cancer, she has become much more organised, much more ambitious and even starts cleaning up her house, caring more about her home in general!! With so much Gemini in house 11, that was almost non existent.
So the earth quality is slowly being established and emotionally she is also slowly becoming more caring, but the motherly feelings, mmmm....., after 1 hour with my granddaugter she has enough, so own children are not high on her list!.
So I would think that by progression these people can start getting in touch with these lacks of element in their personality and because the intellectual faculty is often strongly emphasized, they can also learn to become more organised (Earth), even though it is not easy for them. But they cannot learn to become more emotional of course, at best you can loose the fear of letting go when it comes to showing your feelings.
In her career however, she has always been very precise and orderly (Sun in 10, the only Earth house with a planet) so I guess that any planet placed in a house of the lacking element (am I saying this right?) will behave more according to the lacking element and maybe here we could find compensation of that element, especially when there is more than one personal planet in such a house.
So I wonder why she does find other Earthy friends to fill up the lack of Earth, but not any Water people and that being confronted with emotional problems of others really puts her off and makes her unhappy (" I have enough problems of my own, I dont need other people's problems as well") and that she really enjoys Earthy people and these usually become very important in her life. I think because she has more planets in Air than fire.
BUT, and now comes the very interesting part. She does get very emotional about 11th house matters, to the point of getting tears in her eyes.
The suffering in 3rd world countries, anything to do with the pain people go through after an earthquake or other ordeal. She once got totally conned by a women and straight away gave the person 300 Euro!! never to be given back of course. Things like that, she just believes the sad stories and falls for ît.
So I guess that the feelings and emotions become more universal, more general than personal, because that is safer for her. She can show compassion and love without being afraid she is doing something "wrong", without the question in the back of her mind "what is he/she thinking of me", just because she does not trust herself when it comes to expressing her feelings. And this without any Saturn-Moon or Saturn-Mercury aspects to cause insecurity.
So I think that a lack of an element causes great insecurity in that field. Personally I have only Neptune in Libra (in 11) and Uranus in Gemini (in 7) so I am weak in Air and I have always felt very insecure intellectually. I need diplomas to show myself (not others) I can do something well, that sort of thing. I want to learn and read as much as I can so I feel more competent but hardly ever open my mouth about anything unless I am extremely sure about what I am about to say.People say I have Emotional Intelligence, but it took me a long time to acknowledge that that was something worthwile having!