Actually lag is mostly caused by connection errors and an excessive large amount of packets entering somewhere in a specific amount of time. A simple example would be the Friends List; you can have endless amounts of people as your friend yet no lag is enduced to the server.
And as far as the Toggling goes for it. I thought it would be obvious enough that in the top thread I stated an 'option' meaning you could easily turn off the option.
And 'noobs' are already begging for items you have in your hand; this wouldn't make it any different as there will always be begging.
To show their items? Well if it's only for the trade tables, then I guess it's a good idea, but if it's in public, I would say no.
Computer Science major? I don't know. What's GS2?日本語が少し出来ます。でも、「Weeb? ??じゃないですよ!
Not everyone wants to have their inventories known, you can say to add an option to hide it but it then defeats the purpose you suggested it be used for, as everyone at trade tables would probably hide it anyway so that you can't demand a certain price.
From a sellers perspective they would demand you offered all you had which could be more than the item you want is worth, and from a buyers perspective you may be trying to barter with the seller to get a better deal which wouldn't be possible if they could look at what you have.
That's true, however it isn't particularly a main purpose of it. As for example I could click someones inventory and pick out a deal for one of my items. It would be an easier way to sell an item you wanted by choosing what you wanted.
This is not supposed to be soley made around bartering for an item - it is more as a way to pick a deal to sell one of your items; as it is easier than afking waiting for someone to offer on your item.