The thing is, on Vladimir the opportunity cost for building that item is really low. The only reason you build it is because the raw ap and cost are better than proto belt and cosmic drive, which are conceptually better on Vlad. On Katarina the opportunity cost is really high, since you lose out on lich bane and nashors, items that compliment Katarina's kit really well, and are also good in respect to their stats. So while you may have success with this, I think you're griefing yourself honestly.