Andy,
If you have a specific situation in mind, it would be helpful if you pass it along. I answered the example that Georg had questions about. Each situation could be very different from any other. What I was trying to get across is; when a player is asked by the dealer to expose their hand, they are not completely at fault when they do so. When the mistake takes place, might also affect my ruling, for example, I might make a different ruling pre flop than I would on the last betting round. A player deliberately showing their cards should, at the very least, be given a warning. Andy, when you say the hand continues, it will be played out to the river but, there might not be any further betting. A player that is misled by the dealer should have some protection from further financial damage. The player that drops his own hand face-up on the table faces the disadvantage of playing with an open hand. They alone are at fault, and could suffer the consiquences.