This is a well written and informative piece.

There are no right or wrongs in this area, but my experience over the years tends to weigh towards the negatives in accepting a counter offer. When a business is faced with a resignation, offering a salary increase or a different job title is often just a knee jerk panic reaction. And from a candidates perspective, surely it's too little too late? Most people aren't going to feel particularly motivated or valued if their resignation is the only way to get a salary increase or promotion. Surely it is far better to value the people that are doing well within the business. 

That said, there are bound to be people's resignations that are good news for the business!