
Or it may simply be a side effect of coming out of a bad mental health episode.
Part of my theory of blocks and mental health challenges is that it is good to be able to step back in complexity without too much change in what I was trying to do.
That may have been what I was unconsciously already doing with last week's Ankerstein NS 2 exercise.
I had also been renewing my acquaintance with Challenge block sets, planning a Block Play post on them as a break from Anker, and I continued with them after I stopped doing Anchor stone building. I still intend to return to them at an early opportunity.

So why when I was ready to return to Ankerstein did I tackle a challenging NS 8 project?
Ummmm ... because that is what I wanted to build?
Sometimes motivation is the critical component.

Although an NS 8, the only notched arch required is the 93aR from NS 4. A 100aR from NS 6a is called for but a 100R from GK NF 6a works fine. And although substituting an unnotched 98R for the 98aR would mean more redesign, and probably require a few more small stones, it would not disrupt the overall lines of the building.
However the 19R and 31R notch-filling stones from the 6a are needed. Pairs or singles of 69R from the Kleine Gernegross can substitute for the 31R stones, and 19R stones are in the Heinzelmaennchen, if you have that. Or if you have GK NF 4 + 4a instead of 6, you can substitute 15R stones for pairs of 19R a couple of places.
However you go about it, it is good fun.
And good block play.