Well it works best if you have more than one buying and selling points.
Like you could make orders to buy something at 0.08, 0.076, and 0,7. Then try to sell at 0.88, 0.94, 0,99. That way you have more chances to get it right.
I agree with this and you need to stay flexible to what the "middle" is, as it is always moving. Thus if you buy everything under 0.80 and sell everything above 0.88 (using numbers from your example) you need to be adjusting your range according to the market.
One thing where I think maybe people fail at is they only value one side of the trade. What I mean is with alts coins, people only value the BTC or LTC component, just as with BTC trades, they only value the fiat component (USD, EURO, etc.). So using an example from someone's post before, you buy in at the top or bottom according to what you values more. People only view trades with what they make in let's use USD for reference. So if I sell BTC at $900 and it goes up to $1,000 many feel they missed out or lost. They don't have the same faith in BTC that they have in USD, so they lost out, or missed the boat, etc.
This is also why when coins go on fire sale prices, you still see people selling like mad. Its "OMG, crash I need to get out now and save what I can" (see the value argument I am making?). Same thing when it has gone up $200 over the weekend, "man I better buy in now before I miss out on the rocket ship". Until you are sure of your convictions and have equal faith in both sides of the trade, you will not make any money.
Now this doesn't imply buying in like a fool if your coins suddenly plunges in value, you need to keep current on events with the coins your trade, was there a major problem discovered in the coins code, a fork in the chain, etc.? If there is no fundamental weakness, only normal market dips and peaks, you need to stay the course and take advantage of whatever is happening in the market at the current time.