Both methods work in tandem. You kkow your stress reliving is complete when you side load the rim when the wheel is resting on its axle and it does not budge. Bit ues joshs method works well. Although i find grasping just two spokes (oppoite each other) is more effective as i can apply a higher load. I get to the end point a bit quicker.
Do you mean grasping two pairs of spokes that go to the same side of the rim but that are at opposite sides of the hub (ie 12 and 6 o'clock positions)? Or do you mean grasping two spokes going to opposite sides of the rim?
Both methods work in tandem. You kkow your stress reliving is complete when you side load the rim when the wheel is resting on its axle and it does not budge. Bit ues joshs method works well. Although i find grasping just two spokes (oppoite each other) is more effective as i can apply a higher load. I get to the end point a bit quicker.