I think the rolling % will benefit DJTT and those unable to get in for a one day sale. (i.e. worldwide and timezones)
Also, the percentages and free shipping work to the benefit of both.
This will also be a kick start to an annual program, that we can plan for and count on, while DJTT grows.
The percentages also work for anything you’ve been planning on and the free shipping is enough incentive to compete with other online retailers.
This may also benefit those who have been on the fence about purchasing, as well as not limiting you to specific items, but allowing you to purchase anything in the store.
This algorithm works for the Brick and Mortar industry leaders, who have invested millions into the Black Friday formula and other marketing programs.
It makes sense for DJTT to benefit from this research, without investing in their own marketing research dollars, resulting in higher online prices.
It’s also the biggest shopping day, weekend of the year.
A decent percentage off, and free shipping, is a good formula for success in the current market and in competition with local Brick and Mortar (+tax) like GC.
The numbers add up, if this aligns with DJTT margins.
That’s up to Ean and the Crew. I hope they got plenty of sleep this week. 
UPDATE: Just checked the 15% Guitar Center Coupon while posting a response in another thread. They are also rolling out the percentages.
15% Friday Only
10% Saturday and Sunday
It seems they are also using this as incentive to drive sales and extend the purchase window.
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