Yes I agree totally. What you are describing in the currency world (Or equities, commodities, futures, options, etc...) would be called a risk/reward ratio. I am currently making a profit. A little less than 50% not accounting for hardware. I generally sell that off when new more efficient hardware is either just released or about to be. That hasnt been happening as much as it used to but this is why I generally dont account for hardware costs when doing a basic daily p/l. Besides I also buy all my equipment used so its not that much. I paid less than 5000 for all 20T...including PSU's. I got the PSU's from my old dell 2850's for free 
I ran all the electricity myself so there was only an additional few hundred in wire, cooling, etc. My elec cost per KwH is also very low at 9.7 cents.
Funny....I had actually calculated that in order to have an acceptable risk/reward ratio that I would need to buy roughly 2.8 PH of hardware. At that level you would have about an 80% chance of finding a block every 36 hours. Anyone reading this should not bet on that number. I ran several statistical calculations based upon my semi-limited knowledge in BTC and a great deal of knowledge in statistical math. So I was close. I was just asking if you would do it....not a guarantee where there are none. Even with 20 PH there is no guarantee however as you said the odds increase linearly. Thats a pretty serious investment though. CoinWarz calculates that with 2PH you would gross $5,704.54 per day. A block a day would be 7k or so. So you are only making a small amount more solo mining but without any guarantee that you will make even that. Whereas if you took the same equipment and pool mined you are guaranteed to make the 5700 a day. I just don't see the the slightly greater profit potential as a better way to go over the slow ride with a (semi) guarantee.
I think I will just stick to pooled mining. I appreciate the answers to my questions. Thank you all. I'm just the type that if I were to lose money when I could have made a profit on the slow boat I would be pretty pissed at myself. I'm an investor not a gambler and the fast buck never works out in the long run
Thank you to all for your replies and wisdom
I ran all the electricity myself so there was only an additional few hundred in wire, cooling, etc. My elec cost per KwH is also very low at 9.7 cents.Funny....I had actually calculated that in order to have an acceptable risk/reward ratio that I would need to buy roughly 2.8 PH of hardware. At that level you would have about an 80% chance of finding a block every 36 hours. Anyone reading this should not bet on that number. I ran several statistical calculations based upon my semi-limited knowledge in BTC and a great deal of knowledge in statistical math. So I was close. I was just asking if you would do it....not a guarantee where there are none. Even with 20 PH there is no guarantee however as you said the odds increase linearly. Thats a pretty serious investment though. CoinWarz calculates that with 2PH you would gross $5,704.54 per day. A block a day would be 7k or so. So you are only making a small amount more solo mining but without any guarantee that you will make even that. Whereas if you took the same equipment and pool mined you are guaranteed to make the 5700 a day. I just don't see the the slightly greater profit potential as a better way to go over the slow ride with a (semi) guarantee.
I think I will just stick to pooled mining. I appreciate the answers to my questions. Thank you all. I'm just the type that if I were to lose money when I could have made a profit on the slow boat I would be pretty pissed at myself. I'm an investor not a gambler and the fast buck never works out in the long run
Thank you to all for your replies and wisdom