TTAv
(Time Travel Attack Vector)

I'll try not to take much of your time with this Idea:

Inspiration:
I Play an Old game, called OGame (ironically), for 20 years now,
and I developed and attack there called TTA...

Introduction:
BTC and Blockchain are two interesting concepts...
But I think BTC is in fact a trap...
And Blockchain is the main player here!

So:
Let's say, we've been mining BTC for what? 15 years... and now we have (A LOT) more performance then when we started...
What's stopping us NOW, from re-riting the Blockchain from the genesis block, with 'new' valid blocks?
and come up with a longer valid chain?

Let me Explain:
Say you have COIN1, that has been capped on performance untill now...
But NOW you can go BACK, and re-mine those first blocks at a lower 'performance cost', and still make them valid!
You could create a longer, valid, accepted chain than the one we have now...

I'm assuming all software clients have a preference for the longest valid chain from the Genesis...
I'm also assuming we coud "fake" some information along the way, and still come up with valid Blocks... like:

- Timestamps
- Transactions >> blocksize
- etc...

So my question is:

Is this too far fetched? 
Or do you see this as a problem too?

Take Care,
Yasuke Nakamoto