abruce1000

So we all know a sensibile investment strategy is to dollar cost average into an efficient market portfolio (like the S&P) over time and realise slow / lower risk steady gains over years. However, what if we used this same strategy but in a spread bet / cfd account. Biweekly / monthly adding to a position at whatever price into the S&P 500 over time, would we make huge gains? The logic being that (granted economic outlook is highly uncertain at the moment) in 33 of the last 40 years the S&P has increase yearly and averaged returns of 8%. These of course are modest gains usually but would be amplified using a spread bet or cfd platform. I acknowledge I could be missing something obvious, but I'm pretty sure the S&P will reach 4000 this year, so why wouldn't adding a 1 lot position into the s&p (which usually goes up) every 2 weeks forever work?