I think this is a feasible idea. Maybe theres even no need to roll out any additional infrastructure for this new tier, you could perhaps have these very fflyers use the International F lounges (SQ would have to open their Krisflyer lounges), the obviuos priority waitlist over *Golds, and some other marketing gimmick that Im sure they could come up with.

So... lets see... Im a UNited 1K, LH Senator and SQ PPS... I wonder if that would get me qualified as a *A Platinum...???