How to connect two Dell P2415Q 4k displays to MacBook Pro 2016 What's the best way of connecting two Dell P2415Q 4k displays to the MacBook Pro 2016 with TouchBar and TouchID?

I have the monitors connected to an older MacBook Pro currently with two mini-DisplayPort cables. Can I somehow reuse those cables or do I need new ones?

Apple's support page 1 lets me know that:

"Note that although it uses a Mini DisplayPort connector, the Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter doesn't support connections to Mini DisplayPort displays."

So I guess reusing the cables is not the way to go?
I'm not sure why you would go from a Thunderbolt 3 connection to a Thunderbolt 2 to DisplayPort rather than go directly from Thunderbolt 3 to DisplayPort.

A general rule of thumb in tech (and for many areas in everyday life) is reduce complexity to increase reliability.  The best (IMO) solution would be to go from native DisplayPort to DisplayPort.  

The Thunderbolt ports on the MacBook Pro actual have DisplayPort as a native signal (on a type C connector), so this Cable Matters USB-C to DisplayPort 4K  should fit the bill.