Thanks Refugee!

exactly, NOT birth chart but synastry and then only after the lengthy normal practise of chart comparisons, composites, midpoints, house placements etc etc......

I think as we(astrologers) use them more they will become more important. Especially Chiron. Although I only say that because I'm more familiar with Chiron. There was a time when Pluto was something of a "dumb" note in peoples charts, but as time progressed it started to play a more obvious role. For example I know that both of my children were conceived and born when either transiting Pluto was trining my natal Uranus or transiting Uranus was trining my natal Pluto. I think as we study the asteroids their meaning will become clearer and thus they will become more important in natal charts.

Opps. I think I should add that for most people just learning astrology, it is more important to focus on sign placements  and the planets. By the way what do you mean by hypothetical planets?