?? “if you have theories then you don’t need stacks …” … ??

?? but if decategorify then “if you have algebras then you don’t need sheaves”, whereas sheaves actually are good for some stuff … ?? but generally (??? ….) just in how they form a topos … ???? …. ?? so recategorifying, stacks as interesting mainly in how they form a 2-topos ??? …. ???? ….