Dumping spawn variance will increase guild-mob monopolies and doesn't address the issue of camping. The 48h +/- and 24 +/- allow for multiple guilds of all time zones to get a fair shot, but it's actually been abused because of the first to 15 in zone rule; essentially making the 48hour +/- a 10-15minute "get back to your PC" event for the guild that's been in there 3-4 days. Variance also makes sure that these guilds camping a target for 3 days may inevitably miss out on another target (say vox spawned early). Variance isn't a bad idea, it's ultimately which rules it's coupled with that make or break its intended purpose.
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