Do Orchestras Really Need Conductors?
npr.org
npr.org
The Orpheus Chamber Orchestra is one of the few well-known conductorless orchestras. I learned about them from an article in Fast Company, at http://www.fastcompany.com/39214/leadership-ensemble . One of the problem with no leadership at all was "We needed twice as many rehearsals just to try all of the ideas." Orpheus instead decided to organize leadership around core groups, where those groups, or membership in those groups, rotates frequently.
I'm not surprised by the result. Judging solely from my choral background, of course conductors are needed. We're trained from day one to follow maestro's direction, but to listen to our neighbors and blend in. Working with a good conductor and a poor one is night-and-day. If you are just up there to wave your arms and keep time, you're not doing the job. Good conductors emote, use a variety of gestures, know their music very well, are unafraid to take charge, and correct-correct-correct. We performers are there to do what we are told; we know that we cannot hear all the sections as well as the conductor can, and that the conductor's interpretation of the music takes precedence over our own. Not all the dynamics in a performance - by a long shot - are explicitly scored.
For an example from the Fast Company link, "One of the neatest things about Orpheus is that one of its musicians will go down and sit in the audience to hear how each piece sounds to a concertgoer's ears... I've never seen that happen in an orchestra before."
Why doesn't that happen in most orchestras? After all, presumably the conductor also doesn't hear the same thing as the audience.
The conductor has a better shot at hearing the performers then the performers do - I had the experience of singing near the orchestra's percussion section and all I could hear were drums, drums, drums. But the podium isn't all that perfect a listening post either (as you mention), and I'll guess that during tech rehearsal the conductor frequently wears a set of headphones tended by the sound desk.
I started to write more, but realized that I was mostly pontificating, so I stopped. ;)