I'm confused about something.
Here's what I'm imagining:
Phase 1: Establish Large Stake
a] Borrow 1 million USD
b] Purchase 1 million USD's worth of BTS (or 4% of the total or whatever).
c] Send these transactions to yourself a few times, using these votes to appoint different versions of yourself as a few delegates in a row. Play by the rules for now, including saving up as much coin age as possible.
d] Sell BTS for ~1 million, right as your delegates are in a row (you may have some profit or loss here).
e] Repay your loan.
Phase 2: Build Fake Chains
a] Enter a VM/Supercomputing environment where you can easily do many calculations per second.
b] Take the current blockchain from point (1.d), where you have a few delegates in a row.
c] Using the existing 'real' transaction history, build several thousand parallel chains, one with the 1d sale transaction (which is broadcast), but all others without (which are private).
d] When the last delegate-controlled-by-you is up, proceed to Phase 3.
Phase 3: Profit
a] Broadcast the fake chains, and have your last delegate sign them all quickly (you won't even have to validate, as you know your own chains inside the VM). The thousand attack-chains are now the longest, but none include the 1c sale transaction. Have your delegate refuse to sign the 'real' chain (although you can claim he just 'did not get to it' in time with so many other chains to sign).
b] The next delegate will pick the longest chain (the attack chain) and sign it.
c] One or all of your delegates will be fired (or, possibly, the average user will never notice that anything happened, and none will be fired).
d] In a few blocks, double-spend-sell BTS in step 1d for 1 million.
e] Free million!
What are the problems with this?