Nope never -- I have read all these posts where people do this only to find something is wrong and they have lost the reservation - so they are ticked off and are not able to eat where they had reservations.
Instead I write down my confirmations, take them with me, and that is that. I have had several occasions when I have arrived at the restaurant and had them tell me the reservation was cancelled or whatever and I just show them my confirmation numbers, time, etc and tell them it wasn't me who cancelled. I have always been seated.
Liz