Thank you very much for that! That might explain why one of the macbooks I installed Windows on seemed to have laggy screensavers, whereas the others (Air) seemed to work just fine.
I installed the MacOS Lion installer from a memory stick to the internal SSD (partition 1), Mac OS Lion itself to partition 2 (minimal size) and Win7 to partition 3 via Bootcamp, and it works well, aside from laggy screensavers on one of them, and losing around 10GB to the Mac Lion installer partition 1 (I don't know if there's a way to force it to install MacOS to 1x partition, rather than 2x, while fully offline)
I installed the MacOS Lion installer from a memory stick to the internal SSD (partition 1), Mac OS Lion itself to partition 2 (minimal size) and Win7 to partition 3 via Bootcamp, and it works well, aside from laggy screensavers on one of them, and losing around 10GB to the Mac Lion installer partition 1 (I don't know if there's a way to force it to install MacOS to 1x partition, rather than 2x, while fully offline)