I think grammar is important, but it depends on the situation. I am from the deep south. Most people in my area uses horrible grammar. If one grows up surrounded by people who use language incorrectly, he or she will be greatly influenced by the region in which that individual grew up. It does go to show the level of education, an individual has by the language he or she uses. With that being said, the list of acclaimed writers from Mississippi are as long as my arm. If one reads William Faulkner, it doesn't take long to realize that if a grammar teacher was to grade his writing it would take several cases of red ink pens. Faulkner is one of the most acclaimed writers in American history regardless of his grammar.
If someone is talking to friends on a friday night, will it matter if an individual uses the rest of the extinct subjunctive modus of the verb were? I don't think so. If someone is doing scholarly research, I think the answer is yes.
My Achilles Heel has always been spelling. Thank God for spell check.
Here is my resource for grammar.
1. Harbrace College Handbook
http://www.textbooks.com/BooksDescription.php?BKN=286744&SBC=LCC&network=GoogleShopping&tracking_id=9780155039483U&utm_medium=cpc&utm_term=9780155039483U&utm_source=googleshopping&kenshu=23b2fc57-f886-5d69-42fe-00001827cdd2&adtype=pla&kw=%7Bkeyword%7D&gclid=CJH1ise_kLUCFQuynQoduUEAig
It can be bought cheap and uses example sentences we non-grammar minded folks can copy and reword to fit our needs.
I also think the Oxford Comma is of great value, and it's importance is being eroded by modern writers.
Here is two examples
- We invited the geniuses, Pastor Russell and Judge Rutherford to the meeting.
Without the Oxford Comma, the sentence means Pastor Russell and Judge Rutherford are Geniuses invited to to a meeting.
- We invited the geniuses, Pastor Russell, and Judge Rutherford to the meeting.
With the Oxford Comma, the sentence means more than one Genius and Pastor Russell, and Judge Rutherford are invited to a meeting. Sentence two also has the potentiality of being true. (That was an apostate nerd joke, get it)
Here's a question which sentence is correct.
I wish I was taller.
I wish I were taller.
Defiant.