Mentor Blackjack Counting System
The Mentor count was introduced in the book "Blackjack Bluebook II" by Fred Renzey, who had previously introduced his "KISS" system in the first "Blackjack Bluebook." It is a level-two count that is designed for players who are interested in a healthy balance between playing efficiency and betting efficiency, and also perhaps moving up to the kind of count that might make more conducive to play at a professional level.
There are blackjack systems and strategies that are more favorable for single and double deck games than for show games, and vice versa. The Mentor card counting strategy is designed to be flexible between the two. Obviously, because it is in fact a level-two count, is a more complicated count than then KISS series of counts (KISS I, KISS II, KISS III) that Renzey has also published.
As for the card tags, they require that the player count the 3, 4, 5 and 6 as -2, the 7 and the 2 as -1, the nine as -1, the ten value cards (10, Jack, Queen, King) as -2, and the Ace as -1. The eight is neutral and is not counted, which is the case with almost any other blackjack system.
Like most level-2 counts, the Mentor blackjack count attempts to be a more accurate reflection of what the value of the cards really is to the player. For example, while it is very beneficial that the cards that are 3 through 6 are removed, the removal of the 2 and 7, while beneficial, are not AS beneficial for the player. Therefore, they are tagged at +1. Likewise, removing a nine from the deck is not as detrimental to the player as removing the ten-value cards, which are of great benefit.
The Ace, of course, is another story in the Mentor count. Experts often disagree about the value of the Ace; there are some who think it should be neutral in the count because in playing situations, it can be of benefit to both the player and the dealer. Others believe it has much more betting value for the player, and so it should counted as a negative card. In this system it appears there is something of a compromise being made. That's why it is "priced: at -1; it is taking into account the value it has to both player and dealer.
The strength of any blackjack system is most strong tied to its ability to identify betting situations. In that way the Mentor Count scores points. This system has a pretty solid betting correlation (.97), which compares it favorably with some of the level-two systems. It is much better than Lance Humble's Hi-Opt II blackjack system, for example, which registers at .91. The playing efficiency rating is a .62, and the insurance correlation is nice, at .80. There is a true count required, and that is done by dividing the count by the remaining double decks. If you're switching over from another system, this will be somewhat awkward, but like anything else, the Mentor blackjack count calls for practice, practice, practice.