I will never forget when the professor of a class I'd made a C in told me she'd happily write a letter of recommendation for me, because she knew my grades had nothing to do with my future.https://twitter.com/mckellogs/status/937377243671793665 …
Some of the most capable, brilliant and subtle people I know were horrible at taking exams. An applicant is never just a handful of grades. However, portfolios can matter, they may truly show what you are capable of!