The part I'm still confused about is it possible to have all the Steem power being mined go to a single Steemit account?

Most steem power will go to the account that comes first alphabetically. It's only if you find a PoW while that account is already in the miner queue, that the next account will be used.

Using mutliple accounts seems kind of awkward for using the social network. With your method in order to consolidate your Steem Power you would have to power it down and wait 104 weeks to transfer it all to your main account right?

Exactly. This is not a limitation of my method, it's a limitation of either the protocol or the miner implementation, but there's currently no way around it.

Can you mine from multiple computers to the same remote witness instance?

Yes, and this is exactly what you should do. Only have one witness instance for each account (they may be the same node though, which may also be miner at the same time).