Setting a session persistence sounce very reasonable to me, but why this only affects the Mac client and none of the others is weird. Have there been any (recent) changes on your (Mac) client version or View setup or this traffic-manager? Because it used to work fine on my site, but in a period of time (can't really tell when) the Mac clients stopped working (they are heavily outnumbered, compared to Windows as a client).
I do wonder how much the IP-based persistence will prove a working solution if there is more than one client behind a NAT router (offsite of course).
Thanks for the update