My standardbred doesnt need a harsh bit, actually he works very well in something that is soft. So I use a jointed pellham. Its very soft because the bars are thick and mild, however my horse has a big head, so the bit itself is actually heavy in weight. The curb chain is there really I use it to get his attention if he ignores a small aid, so that I don't have to use a much bigger aid, just had some curb reign. I consider it a very mild bit for him. My hands are usually very soft in my riding in general, so he doesnt get snapped in the mouth, and he goes very very well in it.
Its all in how its used =)
IDK what others think about pellhams, I've heard ppl don't like them, however I've also seen them used very very very wrong =/