MJD,
To be honest, it's been pretty grim. To be even more honest, it's taken some measure of pharmaceuticals to keep my emotional balance. A couple of posts back I went on a tirade trashing lekkies in an over reaction to someone who I thought was trashing engines. Upon reflection and investigation, I found to my horror that that was not the case, the poster was doing a tongue in cheek thing. You know that old commercial, here's your brain on drugs, showing eggs in a frying pan? Dead on.
The good news is that I'm getting weaned off the stuff and things are getting better. Engine work is the best therapy of all and beats basket weaving by a large measure.
Back to the VA. Your fuel is spot on. Most blends are shy of castor but as they are only 17% total oil, they benefit from adding castor to up both percentages.
A good many years ago, I had this experience with Sig fuel. I ran Sig's all castor ( 20% oil) 10 % nitro and got some nice numbers. At the same time, I tried a spiked, (with extra castor) blend that had 25% nitro. Got the same numbers on both. Sig is the best, 1/2A fuel that I've seen. Is their castor better, or was the true nitro content of the blend not as advertised?
No matter, I have settled on 25 % Cool power with extra castor to take it up to about 23% total oil content.
On Norvels, which do well on an all synthetic fuels, I've found that Cool Power delivers a lower, reliable idle than others, even their Omega, castor/syntetic blend.
Have not used Sig fuel on Norvels, as it's hard to get, (for me) and I save that for the VAs.