I just found wrote about the 5C birth spread and it´s unmatched capacity for complete rebuild. In that I was pondering over the role of the sevens, and now want to choose a metaphore that I think may change your perception of them.
Of course Ernst teaches us that there is a 1 within a 7, since 1 to 7 sums up t0 28, which equals 10, which equals 1.
But here is another image: In the body we have a cell called osteoclasts, and their whole purpose is to break down old bone tissue, preparing the track for newborn bonecells.
That´s how a seven work. Ernst Wilhelm, a 7 of Clubs, being the most obvious example. First he tears down any system he learns, and then he rebuild it.
Or, again, 5C: it seems tough to have 7D as the Mercury card. Nothing seems to work out. But it´s actually all about renewal: it doesn´t work UNTIL the old ways have been destroyed and the new ways are starting to express themselves.
Staffan