Immediately I searched on Cricinfo - interestingly the study uses batting averages to compute it's own definition of Valuable. All statistics below are courtesy to Cricinfo.
Player Mat Inns NO Runs HS Ave BF SR 100 50
Sehwag 79 135 5 7039 319 54.14 8630 81.56 21 22
Dravid 142 245 28 11490 270 52.94 27133 42.34 29 58
Sachin 169 276 29 13837 248* 56.02 48 56
Kambli 17 21 1 1084 227 54.2 4 3
Sunil 125 214 16 10122 236* 51.12 34 45
First point, it takes only 17 tests for Kambli to be one of the most valuable players in Indian cricket history! Shouldn't there be a cap on minimum number of tests played to feature in the list?