A fortunate outcome for England regarding that catch. Or is it a case of going with on field decision? Anyhow, I note that the first test pitch has been declared substandard. Rightly so, and credit should go to players for getting a result on it!
With reference to the catch the third umpires role has changed, once the on field umpires refer to the third umpire, the third umpire decides the outcome. The on field soft signal is made in case Of technology failure, ie ultra edge not working, there being no camera angle available etc.
In this case i dont think technology failed it was just the third umpires interpretation of what happened from the pictures he was given, correct or incorrect.