As a teacher of writing to undergraduate students I would always advise would be writers to get an agent and have them assist them in getting a publisher via the traditional means. This process is the accepted way of getting into the writing industry.
There are many stated virtues in having an agent. Once obtained, here is an individual 'in your corner', to promote your work and put it in front of those who can take it further. The agent's mysterious ways and connections can open doors with a secret handshake or wave of a pen. By knowing the publishers, representing other clients and the interests of the market, the agent becomes part of the mechanism and so, a preferred way for a publisher to deal with a writer. These days, few publishing houses accept 'unsolicited' submissions, a sign there are few opportunities to bypass the links in the chain.
However, both roles are components in a procedural chain that deliver a writer's work to a the bookshop and ultimately, the reader. Both roles should perform particular functions, enabling the writer to maximise their potential. Where those roles aren't fulfilled, or the publisher and agent actually hinder the writer by limiting them from particular markets or where they don't pick up certain sections of bad writing, then you have to question the value of an individual fulfilling that role.
My own experience of agents and publishers is wholly negative. Despite demonstrating that my work is a) readable, b) sells and that c) I'm prepared to promote and edit myself, I remain unrepresented and not picked up by a traditional publisher, which often shocks my colleagues. I got my first publication offer back in 2000, but it turned out to be a waste of time and I'm glad I didn't take it up. My last round to agents and publishers occurred early this year (in 2013) and proved ineffective. A part of me is disappointed by that lack of opportunity, but the perennial courting of an 'expert' without any proof as to their ability to help other than a few names dropped here and their smacks of blind faith and wishful aspiration.
Ultimately, in my writing, I am the creative talent. Any return to be made through representation is on my work. I get that there is a need to submit work to achieve representation and that writers find themselves in a crowded slush pile. However, through that process there is also a temptation to pause on writing and editing to 'wait to hear back' or to build up your hopes on the response. Neither of these choices is productive.
Where I have spoken with others about agents and publishers, I have also heard very little that is specifically positive. The general process is well known to me, but when you see fellow writers limited by representation when they should be enhanced by it, you start to question the process.
I'll make a couple of points here. Firstly, I'm not really talking about plot and story changes. I'm aware of percentage change deals in movie re-writes, production company requirements for actors, watershed content, etc... Personally when an opportunity to reach a larger audience comes in, I'm entirely happy to discuss story changes and be as flexible as possible to try and accommodate what other people think is best.
Secondly, I've advised several writing friends on their manuscripts and subsequently seen them signed by both agents and publishers.
Innovations in e-book format and print on demand, allowing writers to reach their reader directly are an excellent democratising experience of publication. I hear many people say 'I prefer a physical copy' when e-books are brought up and other's bemoan the quality of the Kindle genre sections, but this innovation and printing companies like Lulu or Blurb bring the means of production to the writer. Granted, no writer should think about publishing anything without good editorial support, but the availability of this is not exclusive to publishing companies either and the amount of books that make it to the shelves lacking a robust edit is significant.
So, if you are looking to publish your writing? Or make a career from it? Look carefully at your options and don't pin yourself on one response. Similarly, remember you are the creative in the process and there is a value in that.
As for me, well if you're wanting to make me an offer Mr Agent or Mr Publisher, go ahead I'll listen as I would to anyone, but I'm not going to spend more time trying to find you right now as I've stuff to write and please recognise, I'm a bit burned on your process.
Nothing personal you understand. Email address at the top ;)