That's too bad it hapenned that way, because Horary just like any othe rbranch of astrology is a Divine Science. If we humans are incapable to live up to the requirements of a such divine art then it is our fault.
In spite of the widespread opinion the horary astrology isn't simple or easy to master. If the experiences your friend had with horary were disappointing I think it is astrologer's fault.
It is shameful to know that there are horary astrologers, when they give the wrong answer, blame it on the client/person asking the question, instead of admitting their limited capacity to delineate correctly a horary chart.
Nobody is perfect and all astrologers make mistakes, just like all professionals - each one in that field of activity.
My opinion is that there are no wrong horary questions if the interest is genuine, sincere, real... The idea that an early rising degree invalidates a chart is wrong, it is an reminiscence of the times when the astrologers were unable to precisely compute the house cusps, as they're doing it all by hand. The point in those cases is that the question is asked in an early stage, the question hadn't time to grow old in querent's mind or the situation is at the very beginning. And so on for each of the so-called "considerations before judgement".
Astrology WORKS non-stop, each and every minute and everywhere. It is an intrinsic law of the Universe. The only filter a horary astrologer should have is the "QUESTION FILTER". The astrologer should discard all questions that are unethical, stupid, lacking interest, coeherency and so on. Once the horary astrologer has accepted the QUESTION and has drawn the horary chart, there is no way that the chart would be invalid.
However, the astrologer may lack the knowledge, experience or intelligence to UNDERSTAND the chart's indications and then EXTRACT the right answer from the chart. This is something different.
We are all learning, and for one I publicly declare that there are horary charts that I get wrong, I'm sorry for this, but it happens.
Study horary by yourself and you'll see that it works very well.