Haha, yeah, you caught me generalizing too! It is a really long length of weld with those subframe connectors, and that definitely can have its own shortcomings. But of course there are a ton of variables just with the weld as you mentioned.
There are pros and cons to both styles, both from an engineering standpoint and a general installation standpoint. I certainly can't say which is better, and I've installed both. But I think either kind is better than nothing at all.
That is the truth! That damn ground gets in the way!
Although some of aircraft materials engineering is making sure that when the materials DO fatigue you can catch it on the inspections. Because they do fatigue and parts do have to be replaced over the lifespan of the airframe. A notable exception was that Hawaiian Airlines flight that had the section of fuselage rip off- catastrophic failure due to rapid crack propagation. Turns out the cracks were being hidden behind the heads of the rivets of the panel, a materials problem because the metal could fracture small enough to be hidden behind the rivets but still achieve enough of a crack that it would propagate. Other part of that issue was all the short hops, the number of pressurizations became more important than the number of flight hours, and the hours were the inspection threshold.
