I Believe solar lag was fixed some time ago.
He refers to people spamming thousands of Solar Panels. 'Sort of no noticeable lag' * infinity = lag, and there's not much I can do about that, unless nerfing solar panels to a degree where people stop spamming/using them.
I would like to suggest adding a config option to allow/disallow CASUC? Not everybody thinks they are overpowered and some people do like to have that option.
CASUC system will be dramatically changed in 1.105 either way.