But at the least you would demonstrate a perfect grasp of the English language(as there should be no such thing as a second language for you, as you created everything). Now we know this is certainly not the case.
REP: Ok .. so my English is not perfect.
What is the measure of perfectness?
Do we know Dude was once not part of English?
Do we know that English doesnt even shape 80% of our daily communication staple?
What perfection you are asking for is found in your self made dictionary which was never supposed to remain closed.
It never took an English for a Hebrew Scientist to interact with Muslim World.
The love of language is good by the extent of its utility.
Anyways since you have asked this question let me give an analogy from Maths.
If you ask me to tell you 10000th value of PI then I will not be able to give you the answer immediately.
My answer will be delayed by time x but it will be available if this is the only requirement to fulfill.
In principle I say I know but pls give me sometime to give you the answer.
Now since we are using Finite Velocity to communicate .. we say the Universe itself can not give you all your answers immediately.
But Myself and my creation can give you the correct answer after some time.
Same applies to English .. I can learn it and in principle I can be better than the best.(assuming I am not good at it.. though I feel I am too good and actually the reader reads more than the given)
Thus
Knowing exactly correct English is no Knowledge at all.
Communicated part constitues the Universe and not the Language ..
And I guess I have communicated very well.