That language does not appear include Mobile DJs whose performance lies outside the bounds of §106(4,5) and §114(b). As a mobile DJ the licensee is your client, and for private events that client's specific performance rights are enumerated in other sections of Title 17. So, it leaves open the question as to whether Mobile DJs are in fact the intended users of the permissions granted.
If you think that sounds far fetched - then consider the fall of karaoke distributors in the U.S. which is largely due to their claim and applications of permissions not granted, and copyrights claimed but not obtained. They survived while flying below the radar, but were shot down while expanding a campaign of chasing damages for which they had no legal standing. Karaoke makers had paid only for the statutory compulsory music license (something any one of us can do) but did not acquire any legal license or permissions to synchronize video or text, nor did they acquire the publishing rights for the lyrics.
The point is - record pools come and go, and your subscription can be revoked at any time should the class of user be found outside the intended distribution.
Personally, I prefer extended mixes or dance mixes rather than remixes. I only use mixes that stay as true as possible to the original popular radio release. When a song is popular audiences want MORE of it - perhaps even broken down a bit, but not mangled pieces interspersed with unrelated stock rhythm and drum sequences.
I also prefer to mix live adding my own effects and tricks which again - stay true to the texture and character or the original popular release. Mash-ups in particular are segments I would do only in very short length, usually as a way to ignite anticipation of the next track. It's even possible to do this subliminally - using just the right piece at a subdued level. In clubs I learned that doing this often triggers requests for the coming track which the listener was not even aware they had just heard a piece of. The result is that people perceive the DJ as immediately responsive to their wishes, or more intuitive, when in reality it's a mutual trek of samples and measured response.
