I don't want to have a vague understanding.
Yo programmers here have that and look, you can't even program a simple coin to work right. Do you get it?
All you need to know is that blockchains are INSANELY expensive to secure, so much so that even using merged mining alongside bitcoin so that the world-record, world-leading amount of hashing power directed at bitcoin can secure a chain while still also securing the bitcoin chain, STILL most of even the merged-mined coins have not been able to afford enough hashing power to come anywhere near being "secure".
Part of the reason for the coin freezing approach used for the Digitalis Open Transactions Server is the simple fact that most blockchains are far from secure. If any of those frozen coins moved, they would lose the security provided for them by the many hard-coded checkpoints that have been coded into coin clients since the coins were frozen to issue tokens on the Open Transactions server.
Even if someone managed to 51% attack a coin, reversing a transaction on a blockchain, the frozen coins the tokens on the Open Transactions server represent should not be affected, because they have not moved since many hard-coded checkpoints ago.
Even if we imagine bitcoin itself to be secure, which does not seem that bad a bet though what happens with ASICs could maybe change that prognosis, the second-most-secure merged mined chain, NaMeCoin, has vastly less hashing power securing it than bitcoin, and the next down even less, and the last few have pathetic amounts of hashing power securing them (and thus ridiculously low difficulty, making it easy for even small miners to collect nice stockpiles of them currently.)
So maybe possibly one chain in all the world might be secure, maybe if one is optimistic one might imagine two are, but in general blockchains are not secure and the more there are that cannot be merged mined the less secure most of them probably tend to become.
So it is pretty much gross negligence and dereliction of fiduciary duty to spawn more blockchain based currencies.
if you really do have a background in banking that ought to be understandable?
-MarkM-
EDIT: if/when a verdict comes in regarding proof of stake offering any actual security maybe proof of stake might help some a little, but then again might turn out not to.