I really don't like the idea of a display or sip and see shower. I understand that they are customary in some communities. I don't like assembly line, either, when the bridesmaids or someone remove the gift wrap and hand the gift to the bride. How much time does that really save? Personally, I'm not good at wrapping, but I know that many people take great pride in it, and I've heard more than one say she was really disappointed that her hard work got ripped off by a bridesmaid without even showing it to the bride.
Yes, I know that many people find watching the bride open gifts really boring (although I disagree that no one is interested in any gift than their own. I am). And I understand that these ideas are more efficient.
But that's exactly what's bothering me: the focus on getting to the loot as efficiently as possible, in the case of the "assembly line," and the complete elimination of the tiny moment of focus on each of the givers and publicly thanking them in the case of the display shower. If there are so many gifts that it will take forever, in my opinion, you've invited too many people for a shower.
thipu1 put it really well: "Practical, yes. Festive, no."
I mean, showers are just barely acceptable anyway -- the only party that an expectation of gifts can be expressed, because that's the POINT of the event: getting together to give the bride gifts and watch her open and ooh and ahh over each one. True, not most people's idea of a great time, but that's what it is, and if you don't tell people, then they don't bring gifts, and you can't do it.
But if you aren't going to do that activity, boring or not, then how can you politely be telling people to bring gifts? I would feel kind of shaken down, frankly.
Although certainly it's better than those "drop off" things we sometimes hear about. That IS nothing but a shakedown. "You are cordially invited to buy Bride an another gift. You won't be entertained or fed, and no one wants to socialize with you; just cough up, deliver it, and get lost." That's where this kind of "but it's more efficient!" thinking can lead.
As I said, "sip and see" and such is customary in some communities, and I'm not saying that they are violating etiquette, at least not local etiquette, which counts, too. In my opinion, though, if you don't want to have a true shower, fine -- not everyone enjoys them. But in that case, have some other kind of party and express no expectation of gifts.