Yes, that's pretty good summary.

"No way" is simple answer to simple question about simple way of installing apps to mmc card :-)

If the answer should be yes than things start to get complicated. Out of many complicated ways how to do it, cloning system to SD card seems the most simple one to me.

Complications stem mainly from these facts:

- SD/MMC card has FAT filesystem by default which cannot store applications sensibly (missing features like permissions,soft and hard links,...) so you can't run stuff from the card directly

- card is removable so the system would need to cope with card removal in the middle of running something

- installed applications are intermixed with system files and whole system is just a set of packages with dependencies between them so you 1. cannot separate them easily and 2. will break dependencies if you install part of the system to card and then remove it (and even insert other card with different set of packages)