First, most firms in China should know the reality: If an Indian firm is in the bidding process, the odds are overwhelming that the China firm is being used as a bargaining chip against the Indian firm. Something that evidently isn't widely understood by China's solution providers is that most American firms require at least three competitive bids. However, if an Indian firm is already in the bidding process, it is quite likely that they have already been selected and all other firms, from China, Russia, the Czech Republic, wherever, are being used to provide a lower bid and benchmark which in turn is used to get a lower price from the Indian firm. Like it or not, that's reality.
Bottom line: Before spending too many resources on proposal preparation, find out if an Indian IT outsourcing firm is in the bidding process. If so, adjust your efforts and pricing accordingly. There may still be strategic reasons for competing; however, it may also be a signal to walk from the bidding process.