Meh… it’s got a cross breeze! 
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Chris, we see this frequently here. Another possibility could be the OSB got wet during construction phase. The joins and seems can expand. They could be compromised.
Your pic is showing other areas of concern other than just seams or joints.
So what are the consequences here? I’d probably document this in my report. I’d narrate what I see and limitations. I’d have concerns about performance of the roof shingles and concerns about degraded or compromised roof decking.
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Thank you.
^^ That.
If you see it in different light, the visual is not the same.
And foil lined sheathing is very common in FL (and other areas, it’s not the problem here. The product in that photo is Georgia-Pacific’s Thermostat sheathing.
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This pic zoomed in…looks like the roof decking or shingles are exhibiting similar issues at the other side?
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This is my bet.
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I’m not betting on the wet OSB,
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Just an opinion question. Does anyone think a conventional roof will have more irregularities than engineered trusses?
Possibly, but not at every single sheathing seam, in my opinion.
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The arrows (maybe others, too.) are the anomalies that I think are telegraphed through from the rafters: (Otherwise, plywood edges are telegraphing through, IMO.
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I would suspect that they used 3/8" roof sheathing (to reduce cost) and did not use the “H” clips between the sheets. Add to that the additional heat from the radiant barrier batts between the rafters and sagging sheathing and telegraphing rafters would result.
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The thinnest it comes in is 7/16 for this product and you can see H clips in the pictures, so I don’t know if that would be the cause. And the barrier is on the OSB, not just between the rafters, but this seems to be a widely used product in some locals, so not convinced the radiant barrier is playing into it, as I would assume it would have been rejected by now. 
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I go with the wet damaged materials. That product has installation cautions about wetness.
georgia-pacific-thermostat-radiant-barrier-installation-instructions-pdf.pdf (119.7 KB)
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Was there underlayment?
Sheathing thickness?
If the shingles were nailed to a damp roof deck, vola!
So how does the foil face at the attic side reflect Heat from the Sun?
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It significantly reduces thermal heat gain in the attic, by stopping it (somewhat) as it passes through.
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