care Emma et al.,
Just a small thought where in your process of theosophic reduction you get 5. There is also another process that you can add to this to take the numerical value further. Its called theosophic extension how it works is dead easy.. lol..
5 = 1+2+3+4+5 = 15
now some of the larger numbers like 19 are a tad more complex but similar process can be applied.
19 = 1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19 = 190
Ironically at this point we go back to reduction ( I never designed the system ...lol):
190 = 1+9+0 = 10
with 10 we can either reduce further and get 1 or see as the magus and the fool in relationship..
Again we can take the 10 and follow through with more extension:
10 = 1+2+3+4+5+6+7+8+9+10= 55
interestingly this also gives us 10 in this example... lol.. (which curiously we also get if we reduce at the start 19 = 1+9 = 10, showing a really strong connection between the sun and the wheel of fortune

)
Anyways its something folks can play with, and you can build a very peculiar reading from it. Especially when you look at the cards. Its also a way of seeing hidden relations between the cards. To illustrate:
5's in the minor cards and the Hierophant in the Thoth are already connected. However with the 5 through extension we get 15 the Devil card, showing a very interesting connection for different reasons. In this case as for one theological concept that ties the two we have the Hierophant, the expounder and keeper of the gates and keys of spiritual connection (seen in other decks as the pope, a vessel of god) in juxtaposition to the representation of opposition the Devil. This lets one see the working patterns of Polarity in motion.
Also tied with the 5th sphere of the Tree of Life Geburah, martial forces and direct action in relation to the 5's we can play further on the interpretive aspects of the cards by looking at these types of relationships. and connections.
Dang i have missed rambling nonsense..lol.. Anyways just a thought to give you something to play about with..
Kindest Regards
Craig