How To Serve Multiple Wine Glass

If one is a waiter how can one serves a multiple wine glass on one tray?

Serving wine glass on one tray is of cautious act for the wine glass might fell out from the tray and ruins one's serving.On my search on the web i found this picture which help waiters on how they can serve wine glass without the wine glass fall from the tray if one waiter slip from balancing the tray.

It is tray that makes the wine glass cared of to avoid falling out from the tray if one waiter have loss balance..

What do you think,is it cool or not?