I tested a guy once about 7 or 8 years ago, well actually I test him 3 or 4 times. It was a 1" plate vertical with 1/8" 7018.
He ran stringer beads as that is what he claimed he was taught in school some years prior to be the way to go. If I recall he had an AA in welding. I checked on him a couple of times as he was welding and his beads looked great. They were flat, straight, and he was filling the groove very evenly. His cover was nuts on. He worked at a decent pace (given he was only using 1/8" electrode) and the all the weld looked quite nice going in.
When I bent the coupons there were several spots that opened up from lack of fusion. He retook the test several times, failing in the same way each time. I had suggested using a different technique, which I use, where much higher current is used and the rod is alternately pointed pretty aggressively into either bevel face when down in the groove, and then switching to a two bead weave for each layer starting from about 5/8 of the way out, again pointing the electrode into a bevel face when either working the left or right side.
At the time I was surprised to see stick beads with such a nice profile peeling off like poorly done short circuit MIG. Up to that point, lack of fusion was not a discontinuity I had readily associated with good looking stick beads. Since, I have seen this a few more times with other welders running stringers.
This welder couldn't let go of the fact that "stringers were better" as he had been told and taught for years. After he failed the 3rd or 4th time, I asked if he wanted to go again. He told me he was done with welding and was going to go back to his old profession.
On another note, modest weaves can be put in prettty thin and flat if the current is up. This allows the welder to move quite a few inches per minute along the joint, even thought the weld may be wider than a stringer.