I suppose at the end of the day it depends what you mean by 'choking', as such it is open to interpretation in a number of ways.
For the purpose of this study, I have looked only at situations where India have been batting in their second innings. This doesn't include games where India only batted once - I suppose none of those would constitute clutch or pressure situations in the way this thread is engineered anyway.
Sachin Tendulkar has played in 102 games where India have had 2 innings. His averages (no, I don't think that they are an answer to anything either) are as follows:
(times batted, not out, overall ave, games won ave, games drawn ave, games lost ave)
72, 14, 46.98, 60.54, 72.71, 31.54
Rahul Dravid, on the other hand, has played in 71 games where India have had two knocks. His averages are as follows:
56, 11, 50.46, 66.60, 86.09, 27.41.
Dravid's figures in the second innings are consistently better than Tendulkar's when India do actually win or draw the game, yet by a similar amount are worse when India lose. That might actually imply that Dravid's the bigger choker when the chips are really down (i.e. when India are really up against it and fail to save the game) but that Tendulkar's the bigger choker when India are in with a chance of winning or saving the game, having to be bailed out by someone else.
I actually think that the figures show that both are quite brilliant players, but both play better under easier circumstances (i.e. when there is less pressure).