Ah I see I've spurred some interest.
I am actually at a Small university. We have a REALLY dense AP population. This was a necessity to get around the signal loss we experience due to the old building we are in. Our walls are all about 1 foot of concrete. And we have many columns that are about 2foot wide squares of concrete. So to overcome all the signal loss to certain areas we have APs stacked relatively close in some areas.
Our Common area is almost the entire first floor of our building. Our reception, visitors, and cafeteria are all located in this area. So it is generally a high use area. This is where we were seeing a lot of issues with Client Match.
My understanding is that some clients were trying to stick to APs that are on the other end of the room while they were closer to other APs. There are certain areas that the signal can pass through perfectly because there is no direct impedence by walls or columns.
I'm guessing we saw some of our issues due to clients sticking to APs that Aruba was trying to shift to a better AP.
However, I also had to enable ARP to unicast. We were saying a lot of traffic in the air, so most likely causing congestion and dropping packets.
Then to top it off, users running Windows 8.1 on Lenovo laptops were not getting the most up-to-date driver for wireless. Lenovo has a testing period on all the drivers they approve. However, when there are issues with drivers this sucks because you have to wait for Lenovo to approve the driver for it to show up on their website or their update application. Downloading the driver for the Wireless card directly from intel was the solution that worked for multiple 8.1 users.
Also, I didn't know that anyone would really be interested but we already had our min TX power set to 3, assuming that our APs would be able to negotiate what power would be best and only use the highest power needed. However, there was clearly some overlap. So making the change also ensures that each AP is at a higher power from the start. Even at their Min they will have a certain area of coverage.
I will be personally tweaking TX power settings to ensure we don't have "TOO" much overlap. In some areas our APs are as close as 30-40 feet apart. (with a concrete column or wall between). AP density was the only way to really overcome the dead spots we were seeing.
Thankfully Airwave allows me to setup a heatmap so that I don't have to walk around with my laptop and HeatMapper. (Though I will for problematic areas. )