uvmenon,
To answer your question, at chennai consulate the endorsement is not mandatory. But I know cases where passport was returned requesting an endorsement and also know cases where they didn't have any endorsement and still got their H4 stamped.
In the cases I know, where the chennai consualte has requested for endorsement, they didn't have a marriage certificate and just had presented the wedding photographs.
The choice is yours and hope this helps.
Cheers,
Ganesh.