AnyConnect Hostscan results exceed default limit

I have a user who is unable to login using AnyConnect. Their screen hangs at the AnyConnect message: “Hostscan is waiting for the next scan”.

Looking at the logs on the ASA I saw the following log:

Jun 25 2014 16:25:21: %ASA-3-716600: Rejected 266KB Hostscan data from IP <10.5.1.50>. Hostscan results exceed default limit of 200KB.

The syslog database says to increase the limit I need to contact Cisco TAC. So I did.

Cisco TAC gave me the following commands which fixed the issue:

ASA(config)# service internal
ASA(config)# webvpn
ASA(config)# hostscan data-limit <size-in-kilobytes>

Additional questions I asked Cisco but there was no answer:

Why is this a secret command?
My current hostscan only checks one registry string. Why is it generating more than 200KB of data for this?
Why is the default setting not good enough?
Why is this only happening for some users?

AnyConnect Hostscan Results Exceed Default Limit