I don't have the expertise to carry on.
I was hoping you or another expert would explain. As I recall from earlier discussions, when a suit is made the ironing is an integral part of the construction. Simply steaming the suit destroys the considerable amount of tailoring involved in how it is pressed, and how that interacts with the sewing, fit of shoulders and back, etc. It might get rid of some wrinkles (don't know, never tried), but the damage done would require the attention of a tailor to set it right. Pressing, at least when done by people who know what they are doing, avoids these problems. But it is apparently also possible to ruin your fit and drape by incompetent pressing.
Jeffreyd gave pointers on how to touch up a suit in this thread
http://www.styleforum.net/t/88504/guide-to-touching-up-your-suit-without-wrecking-it
This was another that featured a discussion of how suits are made, which explained why bad pressing or steaming at all would undo what they tailor had done.
http://www.askandyaboutclothes.com/forum/showthread.php?97814-Suit-Wrinkle-Advice
A video from Anderson and Sheppard on pressing a coat. This is a guy who does this for a living, uses an assortment of surfaces, cloths, and brushes. He suggests being sparing in pressing, and recommends returning the suit to the tailor when it really does need to be pressed.
http://www.anderson-sheppard.co.uk/cloth-craft/films.html
Even before reading all this, I have left well enough alone. The suits really don't seem to wrinkle much, and they smooth out just being hung to recover. This works fine for travel. Now, knowing a little bit more, I am sure I don't know enough not to ruin a suit if I were to try steaming or ironing. I don't have any expensive bespoke Saville Row suits, so shipping my suits off to a tailor for pressing would be crazy. So I let them hang.
Edited by dbhdnhdbh - 12/6/12 at 3:24pm