If I am reading this correctly, this will be similar to RA's AOI? But without the ability to use arrays in a "nice" way? My DmD experience is subpar at best, I still get a bit lost on data blocks vs arrays in something like Psuite or RA. I guess they're all arrays, just look a bit different.
If this is similar to AOI's I may have to continue trying to make me and DmD get along, it seems DmD will get there sooner than Psuite at this point. I really miss that from RA and copy/paste + find/replace get's old after awhile.
In the AOI's of the other guys, you set the parameters as in or out which can only be used by the AOI or in/out which can be accessed outside the AOI. If I'm off base, someone else can correct me, its been a few months since I was in the RA environment.
The next step completely out of Host's control (but maybe you have some influence) is tag placeholder like support in C-More. Pair this with what you're talking about and it's the same as RA's global objects. Makes life quick and easyish. Although, if DmD's end of the deal works, there's no reason another HMI solution can't be used that does support this.