it seems to be a mix of things for instance sikkpins interaction shader allmost newer causes this but it does happen occasionally, also it only sems to happen in certain areas so im starting to suspect
a fault in a map or brushmodel, maybe a bug in the tools used (dmap i think ?)
strangely enough the function Doom3 uses for shadow occlusion lies in the dmap compiler code and it seems to be from a dev at nvidia Oo atleast thats what the comment says.
hmm just checked and its not in dmap but it is from nvidia
// this is the code from Cass at nvidia, it is more precise, but slower
return R_CalcIntersectionScissor( lightDef, entityDef, tr.viewDef );
hmm gonna try and see what it does

need to set r_useInteractionScissors to -2 before it uses the nvidia scissors.
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