There are few things more dangerous to a gambler than emotion.
Unless you use it to your advantage and tonight's Chiefs-Stormers game could be a perfect example of that.
Emotional money is like daily bread to bookmakers as every minute of every day some loyal fan somewhere backs their team to win tonight's game, the conference or even the championship.
Consider the poor (literally) souls who most seasons believe this season will be the one for the Warriors and take the admittedly long odds offered for them to win the NRL final.
Yes, its patriotic and yes it is kinda fun. It is also 20 years of losing.
Emotion makes you believe things that aren't true or logical, whereas sports betting is based on numbers and facts. Like who wins, rather than who you want to win. But occasionally emotion can be your nice little profit-making friend.
The best example is in Grand Finals. Grand Finals are full of emotion and potential therefore a cash cow.
Teams that usually score say 30 points per game (rugby) or two goals a match (football) will often go into their shells on the biggest occasions.
Think Rugby World Cup Finals. All Blacks beating France 8-7 with a total score of just 15 points and a winning margin of just one.
You could have paid off a house betting on small margins or taking the under line on a total points bet had you predicted that.
It is because as we all know, it is harder to operate at your best, and even harder to take risks, when you are nervous or excessively emotional.
Which, getting back to tonight's game, is why the Chiefs will probably win but you can make money on the Stormers.
The game is bound to be emotional and that could even extend to the referee Craig Joubert, facing a barrage of Stormers complaints about Kiwi teams slowing down the breakdown by holding.
If he takes that on board it means more penalties and a stilted game, which makes for a closer score.
The real emotion though comes from the match being the 100th game for both Tanerau Latimer and Jean De Villiers, two hugely popular figures who their team mates won't want to let down.
Both team rank in the top five of Super Rugby this season for tackle success (tackles that actually put people on the ground) but neither in the top five for line breaks.
So those tooth-loosening defences topped with two dollops off 100-game emotion and the Stormers with a 9.5 point start start to look a good bet, while the total game score being under 42 also looks a decent investment.
Elsewhere there will be emotion of a difference sort as the Crusaders realise they need to start acting like All Blacks dressed in red while their opponents the Rebels come to terms with the emotion of being embarrassed by the Force last weekend.
That means they really aren't very good and if the Crusaders, even devoid of imagination, can't cover the six point spread against this Rebels outfit they are in bigger trouble than they already look.
Again neither team has been scoring quality tries so under 47 total points looks tasty as the Rebels face a horror five-game stretch which would make anybody, well, emotional.