@Bearhunter, i can back that up. My older brother (mechanical eng phd) got a CGS NSERC but not an OGS. OGS' adjudication varies hugely by discipline. In some it's a straight-up grade-ranking mechanism. In others, you might get reviewed by people in hugely different fields.
I'm in public administration, but my app could have been adjudicated by people in accounting, business management or industrial relations, none of whom necessarily know the first thing about public admin.
There is an element of error - false positives and false negatives alike - in any grant-writing system. But it seems OGS is particularly bad.
That said, I'm happy right now.