Hello Ken,
Glad you're back!
Good questions as always...
After having read all the comments (so far), I resonate most closely to Lopaka's comments ("winnow out the irrelevant", yeah, Baby), though the 2° is way too wide (imo).
Upon looking at other systems (specifically Topocentric Primary Directions and the PSSR), it can be seen that MAJOR events... the big life-changers...are, in fact, fated events.
The client's reality experience of it is often mutually exclusive. The aspects mature in just MINUTES OF ARC. At major events, there is a super-accumulation of symbolically correct aspects with tiny orbs and a cross-corroboration from other systems. It may very well be that using transits, solar arcs, and progressions leaves a large grey area, where being set straight by the client might be an absolute necessity.
As examples,
When my Father died, there were the following aspects: (ALL under 0° 11')
It would NOT take an astrological mastermind, psychic abilities, intuition, NOR any corroboration from me to have been able to see just WHEN this event would happen.
When my Mother died, there were the following aspects: (ALL under 0° 11')
Again, 10 years before the event....knowing nothing about me, except that I had a Mother that COULD die, the astrologer would still have no trouble "seeing" what would happen and when it would happen.
When I got married, there were the following aspects: (ALL under 0° 11')
I don't bring this up to underscore that Transits, Progressions, and Solar Arcs are the smaller half of the picture, but in order to show that many events in life (ie. the big ones!) ARE shown quite clearly and, despite everyone from Evangeline Adams on down having softened the "fate" idea with "free will" humanist touches, MUCH OF LIFE IS FATED. In mathematical terms, as the magnitude (of the event in life) increases, the ability of the client to influence it to go differently approaches ZERO.
I am sorry if that offends anyone, though I am positive that it is so. (I have seen too many events from too many charts that show super-accumulations of appropriate aspects with tiny orbs for it to not be indicative of FATE)
Now, back to the topic, orbs for transits...it seems that most RELEVANT transits will be picked up connected to events with an orb just over 1° or so. Part of the problem inherent in this is trying to use a relatively "sloppy" system (transits) to gain time-specificity. (ie. if your thermometer has no accurate markings on it, you can look at it all day and still have no idea of the temperature)
Remember that many of the greatest astrologers of antiquity, who made some amazingly accurate predictions, were often using Primary Directions. If they could have done this with Transits, Etc., they WOULD have saved themselves from many a mathematically prompted headache! In those days, often, a few wrong predictions, or even one important wrong one could mean that the astrologer's head and his body were suddenly in two different places. They HAD to find something that WORKED. Quite often that was Primary Directions.
Why so few that use Primary Directions now?
1) They're not easy, compared to Transits, Progressions, and Solar Arcs.
2) They require an accurate birthtime. ie. ONLY rectifications (which require WORK), not cleverly articulated rectiFICTIONs.
3) Our clients of today are much less demanding. (ie. they won't cut our heads off when we are wrong and they're mostly not averse to playing 20 questions, so we can backfill what we are unable to see with what we are able to hear)
I sincerely hope that many more astrologers of today take a look into these other systems. I can only thank Isaac Starkman immensely for waking me from a very deep sleep that I didn't even know I had been taking....
Peace
OD'dOnLifeItself