I conducted my own little experiment with the following string: http://www.trade-ideas.com/View.php?O=2_9_0&QNLP=30&MaxPrice=100&MaxSpread=10&MinPrice=1&WN=Buying+30+Day+Low+Max+Spread+.10 It contains a Max Spread of .10 , if you'd like to run the odds and see, just duplicate this one and modify the spread accordingly. Here are the results: MaxSpread = .05 691 / 1468 = 47.07% up $0.01 in 30 minutes; Average winner = $0.1791, Average loser = $-0.229, Net winnings = $-19.9531, Best = $3.48, Worst = $-4.51; Casino Factor = 0.72% Daily summary: 1/28 : -11.0700/100 1/29 : 4.5500/100 2/01 : 6.1000/100 2/02 : 4.6700/100 2/03 : 5.7700/100 2/04 : -28.9100/100 2/05 : -24.7200/100 2/08 : 6.9900/100 2/09 : 4.2600/100 2/10 : -7.2500/100 2/11 : 2.3919/100 2/12 : 8.5500/100 2/16 : 0.5750/93 2/17 : 3.8000/81 2/18 : 4.3400/94 Max Spread = .10 731 / 1493 = 48.96% up $0.01 in 30 minutes; Average winner = $0.1886, Average loser = $-0.2287, Net winnings = $-1.1631, Best = $3.68, Worst = $-4.51; Casino Factor = 13.69% Daily summary: 1/28 : -11.3400/100 1/29 : 8.6100/100 2/01 : 7.6100/100 2/02 : 3.0400/100 2/03 : 5.8300/100 2/04 : -27.0400/100 2/05 : -19.5700/100 2/08 : 5.9000/100 2/09 : 5.0000/100 2/10 : -1.4700/100 2/11 : -0.5781/100 2/12 : 6.7800/100 2/16 : 2.1050/100 2/17 : 8.3500/93 2/18 : 5.6100/100 Number of trades increases by 25. Nothing unexpected present.