We had some great sound men over the years but we found some bad ones, particularly at folk festivals when we didn't have our usual people with us. (I'm talking about Australia). Most of the ones we had complaints about were only used to electric instruments. It was always a giveaway when the soundie pointed at a mandolin and said, "What's the hell is that?" When we started back in the late sixties there was no foldback but as things improved it was a split off front of house. I still think that if all the band listens to the same mix they should be able to balance themselves and make the sound job easy, but most modern systems are unable to give you the same mix front and back. A lot of systems have several different mixes on stage and I reckon this only encourages the innate self-centredness of musicians (of which I'm one) We did a tour supporting Steeleye span once and they had eight different mixes on stage. That's what they like and they had their own soundie and mixing desk to achieve it. I also agree with the previous person who said thank the soundie if he does it well. This is not only good manners, but it helps to develop a relationship with the most powerful person in the venue.