Help for WinISD number of drivers

Hello ! This is the first time ever I post on this forum.
Long story short, I am designing a 2-way speaker enclosure for a friend.
Using WinISD, I simulate the woofer response (http://www.loudspeakerdatabase.com/fr/Dayton/RS125P#8%CE%A9).

Problem is, when creating the projet, I have seen in a Kirby meets audio video that the choose 2 for his 2 way enclosure. But that doesn't feel right.
I have some hints from the frequeny response that makes me think WinISD doesn't think he is placing the woofer with another loudspeaker on the same box, but rather he is simulating 2 times the same woofer.

So I need to know, and I hope someone will come up with an explanation I can't find online.

When selecting "2 drivers" in drivers placement in WinISD, is WinISD simulating my woofer being placed somewhere considering there is another speaker (in my case, a tweeter) or is WinISD simulating two identical woofers ?

Thank you.

These programs simulate low bass response only so the "driver number" in the program refers to the quantity of low frequency drivers to be used in the enclosure. The only relative factor about any mid and high frequency drivers that will also occupy the same internal space is the air volume they displace, as this displacement is not factored into the calculation and must be added by hand. The same applies to port volume displacement.

Edited by Conanski - 13 March 2021 at 5:34pm