Let’s not conflate AOs analyzing course rigor with analyzing grades; at selective colleges, they look at both.
Few colleges will look at a weighted GPA outside of assessing multiple applicants from the same school, because there is no common metric for how classes are weighted. The HS from which I graduated did not weight at all. However, if you look at a college’s Common Data Set, it will indicate the importance they give to rigor, GPA, and other metrics. Villanova and Clemson both weight rigor and GPA as “very important.”
https://www1.villanova.edu/content/villanova/enroll/statreports/_jcr_content/pagecontent/download_0/file.res/Common%20Data%20Set%20Fall%202017_v5.pdf
https://www.clemson.edu/institutional-effectiveness/documents/oir/CommonDataSet2017.pdf
BC does not publish its CDS, but says on its website:
https://www.bc.edu/bc-web/schools/mcas/sites/isp/undergraduate/admission.html