The part about controlling more of the reward pool is technically accurate but realistically inaccurate. That SP wasn't voting on anything prior to being powered down and thus didn't impact the reward pool at all. Your ability to allocate the reward pool is based on total steem powered up, but more importantly, the SP powered up AND voting.

For example, if there was 100 million SP powered up in total and someone with only 100 SP cast the only vote for the entire month or 3 months or whatever the average SP calculation period is in regards to reward pool, that one vote would allocate the entire reward pool. So, it's more than just steem powered up, it's steem powered up and participating. The main steemit account was not participating and therefore their powerdown will not directly impact the value of your vote.