Think of it as lotto numbers. The pool picks a first batch of numbers, and you fill in the second while mining for them. Solo mining, you pick all the numbers. So if you had been solo mining, it doesn't mean you would have found the blocks. You may have found even more, you may not have found one yet.
Thank you for explaining that for me.
So how does one decide if the awards from a pool are better than solo mining?
Solo mining is technically always the highest payout on average. The problem is a matter of scale. At 1 GH/s on the Bitcoin network at this difficulty, it would take you about 8 months to find a block. You get the payment all at once, nothing before you find it. It could take you 4 years. It could take you 4 minutes. But "on average" it would be around 8 months.
The question is are you willing to make a gamble with that kind of payoff time, and are you really sure the market & network speed will be roughly stable during those 8 months? Because if you don't find a block early when network difficulty is rising, that 8 month average will keep increasing. If the market crashes before you find your block, you'll end up with less USD/EUR/etc. than you would have if you had been mining at a pool and selling the whole time.