Do you know what I think?

[Redpig59]

The conductor makes no difference.
I've been watching the Proms, and some tit stands there waving his/her baton around.
Often with no relevance to the music being played.
I think that the orchestra members all know their bit, and don't even look at the conductor.
The music sounds fine anyway.

[Phillip Phlopp]

A conductor makes sure that the orchestra both starts and stops at the same time.

[Julian Mince]

Having played in Orchestras over the years, players tend to keep the conductor's arms in the corners of their eyes to maintain speed. It's a shame that we don't have a conductor for the band to keep our wayward drummer in check.

[Red Baron]

There was a programme a few years back with various 'celebs' learning how to conduct.

It surprised me how complicated it was, the orchestra is slightly behind the conductor to allow them to see what the conductor's gestures are asking for.

Katie Derham won, if I remember rightly.

[Redpig59]

I stand corrected.

[Phillip Phlopp]

There was a bit on the radio about the conductor's purpose.

The performance is preceded by lengthy rehearsals where the conductor imposes their interpretation of the composers musical score. To us mere mortals a performance conducted by one conductor sounds the same as another conductor but to the trained ear of the music aficionado they are chalk and cheese. You can sometimes spot them in the audience with the music score on their laps. I suppose it's similar to a director of a play, say, Shakespeare, and might have directed an actor to put more emphasis on certain words or movement on the stage.

James O'Brien's Mystery Hour is a fount of random information.