At risk of being both off-topic and in the wrong forum section, the above brings to mind the pre-war EF8 hexode, another attempt at enhancing performance with addition of grids and juggling of function. There were evidently some decades of off-the-beaten-track research going on in valve- makers labs with varying degrees of success;
http://www.r-type.org/exhib/aai0175.htm
http://www.r-type.org/exhib/aaa0469.htm
https://frank.pocnet.net/sheets/046/e/EF8.pdf