There is no "mess up" that can't be fixed baring a break in RIPEMD-160, SHA-256 and/or ECDSA. If that happens LiteCoin provides no protection because it uses the exact same primitives. The fact that it uses a different algorithm in mining will provide no protection from a cryptographic break.
I think what this analysis fails to recognize is that could mess up in a way that was not fundamentally destructive to bitcoin but the markets could incorrectly PERCEIVE that it was and lead to a massive crash.
The whole Bitcoin Ecosystem has led a charmed life...
To the point where it's highly centralized in California and Chinese foundries...
And smug Bitcoin Monopolists feel completely immune from any external threat...
All this for an entity with ONE (1) paid Dev.
LOL...
The US Government places a low priority on primitive, low velocity "toy commodities"...
And it takes DOJ several years to gear up on a target...
But a major Govt actions on BTC are in the pipeline...
It's inconceivable that Govts will allow a serious threat to Fiat.
We are going to need 100s of diverse, global, EXCHANGABLE Alts to survive the onslaught...
With 2nd Generation design and protocols...
That don't create centralized monopolies...
And that don't require burning 500 lbs of coal/BTC.