No I'm not a Dr or an MD but Dr. Robert F. Cathcart M.D and Dr. Klenner, MD are and used high dose vitamin C successfully. Some of their results are described in the first link in the OP
links in your post are to scientific studies showing a high intake of vitamin C supplements can increase risk of kidney stones for example:
>Results >During 11 years of follow-up we ascertained 436 >first incident cases of kidney stones. Ascorbic acid >use was associated with a statistically significant >2-fold increased risk (Table). In contrast, multivitamin