Sorry but this is just forum theory crafting as usual in these discussions. Named loot that has two affixes you like and one or more affixes you may or may not like will be treated like almost every other named item.
Evereyone in the game is wearing multiple items where at least one affix on one item is not usefull or ideal or optimal, or is duplicated on another item. Only people with the most generic builds that have a mapped out gear set that fits like a Perfect puzzle and has NOT ONE WASTED AFFIX can say they're wearing named items with zero overlap, or useless affixes.
A named item that has two good affixes and one that's random or semi random is just an opportunity. Like everyone does with "EH" and "EE" versions of loot, you'll equip the less optimal one while you look for the more optimal one... It's an opotunity for that good item to become (with the right random affix) a perfect item that is usefull for a FAR WIDER range of character mixes.
Almost everyone in the game already does this. Except the really odd hypothetical OCD that can not bare to use something unless it has 100% useful affixes with no overlap or redundancy. And I don't think the game should cater to rare hypothetical OCD's
Tell me you've never used a sub optimal piece of gear or version (Epic Normal or Epic Hard) while you tried to get the optimal version (EE) and I'll call BS. A GS greataxe with only two shards added to it? Carnifex before you got your Drow Greataxe?
Are all you Epic Sword of Shadows users running around swinging Starter weapons at 25th level while you farm VON for your eSoS? LOL yeah right I thought not. No you're using a weapon that is not as good as your goal.
In the end this is a theory crafting discussion of people who want predictability or are expecting pure Meta gaming in every aspect of DDO and thus are unhappy with anything that isn't set in stone waiting for them to "farm" versus people who like a little chaos and unpredictability.
DDO's biggest problem is meta gaming... Everyone knows where everything is, and most of us know how to get there. There's no randomness or chaos to make this boring predicatability more interesting. "Farming" and "Grinding" are not fun... They are a means to an end, that is facilitated by 100% meta gaming, the game could use any random unpredictability it can get. Sure this will make some people uncomfortable, those that want their MMO's to be the equivalent to Farmville, rote repetition, always getting the same predictable reward. Quest selection via "what has the most XP per minute and can be run over and over the most quickly" and loot farming via "shortest path from point a to point b". But games don't actually need to do that, and whats more many of DDO's biggest player retention problems are pure meta gaming side effects.
D&D players from NWN came over and saw rote repetition no variety no user content, and a FPS like control setup and they left... Dungeon crawlers and RPG fans, come over and find rote repetition zerging for the fastest way from A to B and ZERO reward or need for exploration and team based tactics and they leave.
More random = less meta and that might be painful medicine to the farmers who actually love to farm, but it might actually be a good direction for the replayability of the game. I support any step that leads away from meta gaming, towards a more organic and un-memorizable game even in small ways like this. Don't worry if you enjoy farming you still have 99.9% of the game that is static and purely meta gamable.