Yep, Waive off the ground crew. Look to the flap handle. FO moves the flaps to takeoff position. Clear of the ramp area flight control check double checking flap position. Taxi Check list. Triple check flaps in TO position, Takeoff checklist one last check flaps are in TO position.
The trigger at Delta to lower the flaps is the waive off. Both systems have a trigger its just different.

Delta also had different procedures then NW in other situations regarding flaps. As a example Delta taxied and deiced flaps up. NW did it flaps down in snow and ice conditions. Most airlines deice flaps up. In Moscow they will not even deice a aircraft with the flaps down. We adopted the NW method however I was still able to leave Moscow because I knew as a Captain at Delta I had the authority to put the flaps to up to deice. The choice was that or stay until spring. I prefer to have some authority and choice.