Minderwiz
Ok now my comments and questions:
(1) Is this true of all horary charts (and not just this 'generic first house' horary)?
Can the past and future aspects of the querent's significator reveal past and future events? I've noticed astrologers *sometimes* taking the *Moon's* immediate past and immediate future aspect (singular, not plural) but never building a connected series of events from the Ascendant Lord's aspects.
(2) Would one still do this if the First House Lord were Saturn? The previous aspect might lie well back in the past (and well forward in the future). The Sun is relatively fast moving.
(3) Does this 'past sequence of aspects predicts past sequence of events and future aspects future events' idea work only for First House Lord or for any other house Lord?
(4) If this is possible, shouldn't this be done for every horary chart? This would give excellent validation and improvement of technique over time. When did this drop out of the tradition?
Notes:
[1]Modern software (Solar Fire) gives a different sequence, but SF doesn't do moeity so that might explain the difference, I haven't checked.
12:08 February 28 Sun square Saturn
05:17 March 05, Sun conjunct Mercury
15:11 March 11, Sun opposes Moon
10:06 March 14, Sun sextile Jupiter
00:23 March 19, Sun conjunct Mars
[2] Sure the 8th is 2nd of 7th, but also 3d of 6th, 4th of 5th, and 6th of 4th. If the fact that Mars ruled 4th was the deciding factor, the 6th of 4th would be an equally valid deduction. So why not 6th of 4th? conflict with workers on land (say?)
It depends very much on the question that is asked. Indeed, I can't stress too much the importance of the question in framing the response. The question should be well thought out (the querent is supposed to take her or his time to get it right, and may negotiate it with the Astrologer (in order to ensure the Astrologer understands).
Some questions, such as those which do refer to past or present events, as in this case (and in your own Transit question) lend themselves to such a device. Note that Lilly only uses those aspects of this part of the question, though he could well use the reading to inform his other responses.
I've used this technique, but only rarely (because the opportunity is rarely there with the questions I've been asked). The Moon's aspects are more generally used, but then that's because the Moon has signification over the Sublunary world (what goes on down here) and it's much faster in terms of making aspects than any of the others (Mercury, Venus and Sun come next). So if your significator is Saturn, it's not going to be that helpful because it's slowness pushes the time between aspects back considerably compared to the other planets. You're left with symbolic time (which answers your second question).
Don't be afraid to use the technique if the question allows but it's not something that you would do in each and every horary.
You could use it for other houses as well, in answer to your third question but again it depends very much on the question. You could use it when the question relates to the movements of a family member or a friend, or a lost pet, though in the latter case most questions are going to be concerned with where it is now, so it can be found. The same could hold for stolen property, though as there are significators for the thief that doesn't help a lot. Lost items tend to be stationary so it's very rare that you might use the technique there. The use of the Moon for charting past and present events of quesited items might be more useful most of the time.
Clearly, from the above, this shouldn't be done for every horary (in answer to your fourth question).
Incidentally Solar Fire will do moieties and these are adjustable but they are not selected by default. From Chart Options, select Aspect Set and then select moieties.asp