Normally, in full pay deuces wild video poker when the player has the choice of keeping either (1) a deuce only or(2) three to a royal flush, including a deuce and an ace,and there are no flush or straight penalty cards to the royal, the best play is to go for the royal flush. For example, take the following hand: 2 clubs, 3 diamonds, 6 diamonds, Q spades, A spades.
Normally in situations like this the best play is to keep the deuce, queen, and ace. However this particular play is one of the exceptions. Following is a complete list of such exceptions. The exceptions are listed first according whether the two discards are suited and second according to the high card which is suited with the ace. Pairs of discards meeting the exception are listed.
Queen: 3/4, 3/5, 3/6.
King: 3/4, 3/5, 3/6, 3/7, 3/9, 4/5, 4/6.
Jack: 3/4, 3/5.
Queen: 3/4, 3/5, 3/6, 4/5.
King: 3/4, 3/5, 3/6, 3/7, 3/8, 3/9, 4/5, 4/6.
There is another exception that cuts the other way. With 2/A/J/10/7, where the ace is suited with the jack or 10, and the other two cards are of different suits to the royal and to each other, then it is better to keep the 3 to the wild royal, despite the penalty card. Knowing this exception will save you one cent for every $392,584.27 you put through the machine.