I'm afraid your comment about lookup fields in tables being essential is lost on me. The proper method is to have a lookup table, not a lookup field. Sure, you will find many pages that write positively about them; probably because they're catering to an audience that hasn't the interest or ability to do things properly.
Perhaps your post title threw me off, because an index number is what I'd expect to get instead of a value where mv fields are involved. So you are correct in relating .Value to being a mv field issue. I guess I wasn't of much help.
The more we hear silence, the more we begin to think about our value in this universe.
Paraphrase of Professor Brian Cox.