Welcome to the party, Marius. Those are interesting questions, and I suspect there are many possible approaches, but here are mine:
After banging my head on several other alternatives, I now recommend avoiding multi select dropdowns in these cases, and instead, simply create a separate checkbox for each of the entries. In doing so, Workfront can effortlessly filter, group, sort, and chart on any of them; and if and when the time comes to report those items with similar combinations together, simply add a calculated parameter and CONCAT each of the selected values together...which Workfront (huh!) can also then filter, group, sort, and chart. My rule of thumb (especially around charting) is "for best results, persist the data in the data in the database at the lowest common denominator".
Same concept: I'd suggest you pull the Project Owner's Home Group into a calculated parameter on a Project custom form, which is similar to my "http://store.atappstore.com/2010/12/hows-my-portfolio/">How's My Portfolio blog post a few years ago
Serendipitously, I am in a coffee shop this morning discussing this very concept with two colleagues on a conference call as I type this. "No", is the disheartening short answer...but we're designing a solution that will allow Workfront customers to designate that such a custom dropdown be kept in sync with some other object within Workfront, effectively as if Workrfront had a bunch of new parameters you could drop onto a form called "Projects" (meeting your need), or "Users" (another common usecase), or "Users with Brown Hair" (to use a silly example to illustrate the power of this polymorphic approach). Annnnnnnd I've officially taken this one too far. For those who do catch my drift on this last one and are interested in helping pioneer this technique, you're welcome to drop me a line at doug.denhoed@gmail.com.
Regards, Doug Doug Den Hoed - AtAppStore Got Skills? Lend a hand!
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