?? relationship of intersection homology to relative homology ... ??? ....

?? perversity as device for systematically getting alternative core of arbitrary abelian category ???? ..... ???? .... ??? too strong to be true ?? .... ???? reliance on "geometric structure" beyond mere chain complex ... ???? ..... ??? ......

?? inclusion of higher stratum, vs of down-segment of lower stratums .... ???? ....

??? perversity as ... sort of moore-postnikov factorization operation ??? ...... ??? .....

??again (?? ...), any particular perversity acting as "identity operation" from any of these viewpoints ?? ....

quivers .... flag varieties .... ???? ....