There was a guy on another forum who decided one day to test initial seeding performance on a brand new torrent on different clients. It turns out that BitTornado's Super Seeding mode is more efficient than uTorrent's Initial Seeding mode (both 1.8.5 and 3.0.x). Using BitTornado, more seeders showed up after he seeded about 1.2x the torrent size. In uTorrent, it wasn't until about 1.5-2x the torrent size. The downside to BitTornado is that it hasn't been updated for years (perhaps that's a good thing for those who absolutely hate updating software).
Just a bit of fun trivia to add to your knowledge about Super Seeding.
I was always under the impression that, rather than trying to get more seeders (ie. people with the entire torrent) as quickly as possible, the point of initial seeding was to get different bits to as many different peers as possible. In other words, try and get all of file 1 to one person, all of file 2 to a second, file 3 to a third, etc, so that the entire torrent is available from sources other than the initial seeder as soon as possible (and so that the load from other leechers is spread out as quickly as possible, too, since they can all download from each other).
So measuring the time it takes for the first other person to get the entire file is a fairly useless way of measuring efficiency, since it's a totally irrelevant statistic - it relies on the efficiency of the first few peers who get all the different bits of the torrent as much as, if not more than, the initial seeder.
Of course, I could be wrong, but that's how I understand it to work. And it does make a lot more sense, IMO.