Writing "3dB" is conceptually *exactly* the same as writing "200%".
I just checked the Wikipedia article, and it is totally correct, and agrees 100% with what I stated, as does every physics text that I've ever seen. The definition is what it is, and your assertion that "3dB" is exactly the same as "200%" is simply incorrect.
I don't want to repeat myself or belabor the point, but 3dB represents a 2:1 ratio of power, and a 1.41:1 ratio of voltage. This follows simply and irrefutably from the laws of physics at work, and the underlying mathematical relationship of the quantities being measured, be they field quantities or power quantities.
Remember the basic definitions of the quantities, which is that power is proportional to voltage^2, so it is mathematically impossible for them to change together by the same ratio.
When power changes 2:1, or expressed in dB, 10 * log(2) = 3dB,
Then voltage changes 1.41:1, or expressed in dB, 20 * log(1.41) = 3dB.
I hope that you can see now that your mistaken idea that "3dB==2:1 or 200%" for both voltage and power is impossible, because power is proportional to voltage^2, it is mathematically impossible for them to both vary by 2:1 at the same time.
(Just for posterity, a factor of 2 == 3dB *always*.)
That last point that you made for posterity is not correct, because the definition of dB relates to power ratios, and a 2:1 ratio of power is 3dB, whereas a 2:1 ratio of voltage results in a 4:1 ratio of power and 6dB of change.
So, a factor of 2 is only 3dB when measuring power, because for power dB is defined as: dB = 10 * log(P1/P0),
and 10 * log(2) = 3
But when measuring voltage, a factor of 2 is 6dB, because for voltage ratios, dB is defined as: dB = 20 * log(V1/V0),
and 20 * log(2) = 6
I have several pieces of fruit and one of them is a banana
But the statement in the puzzle is: "I have two children, one of whom is a boy born on a Tuesday
Your example sentence is not analagous to the original problem, because the original statement provides two facts about one of the children, whereas your sentence provides only one fact about one of the pieces of fruit, therefore your argument is flawed.
The correct analogy is: "I have several pieces of fruit, one of which is a banana grown in Ecuador."
It is obvious that this statement about one of the pieces of fruit does not make any statements about the nature of the other piece of fruit, and certainly does not preclude the possiblility that the second piece of fruit is also a banana. For example, the second piece of fruit could very easily be a banana grown in Honduras, and nobody would consider the statement about the first piece of fruit to be a lie.
Quantum Mechanics is a lovely introduction to Hilbert Spaces! -- Overheard at last year's Archimedeans' Garden Party