My suggestion: It's an issue of bandwidth while walking... Seems unlikely that anyone would care much about continuing to watch a streaming video while walking room-to-room. If this were the case, then using a single SSID makes for a faster change-over of access points. But it's likely that the signal strength will degrade as the person walks, and get to the point where the stream is unwatchable. Then the client device "may" choose the better access point; or not!
With two SSIDs, the client device "may" react to the too-weak signal and "may" choose the other SSID as it would be in the preferred SSID list of the WiFi configuration. But if the device dumbly chooses again the weak signal access point (or WiFi router), the crummy streaming reoccurs.
So if one simply goes from room A using AP/router A, to room B, then begins using the device again, the two SSID scheme is best. If the device chooses the weaker signal, which some may do, the user can then cuss and manually select the better SSID.
(Enterprise/professional WiFi doesn't have this issue, as systems like Cisco and Aruba have driver software that runs on client devices (PCs, many PDAs, maybe smart phone by now, such as Cisco's CCX). This software expects to receive a broadcast in the beacon of the access points, a list of access points IDs, a "neighbor list" if you will. The special driver software uses this list as a clue on how to do a fast handover to the best AP. This is often done for WiFi based VoIP handheld devices. All this fall-de-rall is needed because the IEEE 802.11 specs don't yet define, nor have vendors adopted a standard for fast handoff as is ever-present in cellular. Even better, managed WiFi networks have means for the clients to be directed by the controller as to which AP to use.)