?? “generic flag pair in building b” as pure dimensional theory ?? … ?? for b any standard building ??? …. ?? simply mod out by cartan ??? … ??? … ???… ?? mention in letter ?? …

?? special case of pairing generic (?? a-series ??? …) flag pair with other (?? prop-like ??? …) structure ?? … ?? prop for iso to constant v …. ??? …. ?? “coordinate system” ??? ….. ???? …..

?? was originally trying to get this to be a toric dimensional theory, but ran into problem with path sum … ?? though in case of 2-by-2 matrix multiplication the path sums are binary and setting them to 0 can be simulated without addition perhaps by somehow conceptually negativizing one of the summands and putting it on the other side of the equation; might this somewhat explain (?? …) why case of projective line seems anomalously simple in some ways ???? ….. ??? … ?? hmm, but what about setting path sum to 1 ??? ….. ???? ….

?? (?? possibly bad, or at least annoying … ?? …) idea of trying to use this as step on way to developing theory of single flag in b …. ??? …. ?? hmm, to what extent is this equivalent to other approaches that we thought about ??? …. ?? pairing coordinate system with feature to get space of features …. ??? …. ?? maybe somewhat different … ??? … ??? different features at least ??? …. ???? …. ??? ….