I tried doing that himani and i didn't suceed in doing so. Now i suggest you do the same and then find out whether it is really going down. And yes, here the question is of kitchen knife. And kukhri is bigger in size than the knife.
Try and try find out for yourself. IF extra pressure of buckets full of water applied with thrust that noice also didn't made Talwar to wake up and see nor even with Mrs. Talwar?? Ask yourself this question. In a country like India lots of proceedings of investigations are botched up. This even a small kids also knows.
Now i am seeing you in the third paragraph a better investigating officer than the CBI. giving reasons and explanations???? and accuse those people who does that trying to analyse Talwars involvement? How could you do that questioning the integrity of others and u ur self is doing the same thing in another way.