I did this with NW once. On the return, DEL-AMS flight was cancelled, so had to take flight 24 hours later. AMS-DTW flight was switched to the nextday without me even asking. I asked airlines about missed connection. They told me that if they were the carrier on both segments they would take care of it. Also that $950 from FRA-BOM is a lot. I normally pay in the area of $650.