Was it me?

I have just read the DPReview of this lens and it would appear from their testing that they did not find this.
https://www.dpreview.com/reviews/tamron-16-300mm-f-3-5-6-3-di-ii-vc-pzd-macro/4
Perhaps your lens was faulty - it seems odd that the critique of it is positive and you found it virtually unusable.
I have had Tamron zoom lenses and always found them very good.
https://www.dpreview.com/reviews/tamron-16-300mm-f-3-5-6-3-di-ii-vc-pzd-macro/4
Perhaps your lens was faulty - it seems odd that the critique of it is positive and you found it virtually unusable.
I have had Tamron zoom lenses and always found them very good.