There is no right or wrong way to use the word shill (or any other word for that matter) as long as it's in the dictionary.

No, it's actually the other way round...
FIRST a word appears in live language (usually it starts in some specific environment: region, age group, subculture, etc.) and THEN this new word (or its new meaning) is racognised and acknowledged by dictionaries (after discussion among experts, where some of them would typically discourage the new word or its new use). But the key point there is that language is LIVE rather than dictated upon us by dictionaries! And if the word becomes massively used even its strongest oppnents must eventually accept and acknowledge it. The same goes with Bitcoin!

I agree with you, but perhaps I worded my sentence wrong. I think this is better: According to English teachers, there is no right or wrong way to use the word shill (or any other word for that matter) as long as it's in the dictionary.
If you think you can turn in a paper for English class filled with slang and improper usage of words (usage that is not in a dictionary somewhere), then you might be receiving a F.

Although there are a lot of slang words which many people use every day, it is still considered improper English to use these words- at least in academia.
And yes, I am growing tired of the shill debate as well. Let's just let this thread die peacefully.
