The Significance of the Placement

I think the biggest thing I have learned about grammar and punctuation in just the last two weeks is that I don’t very much about them. While I would like to think that I do, I don’t. That is not to say that I don’t know my grammar and punctuation though. I know the fundamentals, but I don’t know what is behind those fundamentals. I know that I could tell you that the apostrophe goes there, or that the comma goes here, but if I am asked to explain why, I can’t. I can look back and say that I know my teachers didn’t teach the stuff that is behind the fundamentals, but rather said the apostrophe goes here and the comma goes there just because they do. I wish my teachers could have taken the time to teach all the stuff behind the fundamentals, because I know I would feel a lot better about my grammar and punctuation right now if they had.
The other day I was really thinking about what I’ve already learned in this course and I thought of the first activities that we did in our course books. What I thought about here is how much of a difference a comma can really make. The placement of a comma is so important for the meaning, and I didn’t realize it before. The example that really stands out to me here is this one:
A woman without her man is nothing.
There were many different ways that this one simple sentence could have been punctuated and each way would have changed the meaning of the sentence. Here are two ways I did it:
A woman: without her, man is nothing.
Obviously, with this way, I was saying that man is nothing without a woman. The meaning was significantly changed the second way I punctuated the sentence:
A woman, without her man, is nothing.
This time, I was saying that a woman is nothing without her man.
The two meanings here are completely different, even though the two sentences have exactly the same meaning. Another example of this is the Dear John letters that we did. I was amazed with how simple punctuation could change the meaning so much from a love letter to a break up letter. When I first looked at the letters, I said there was no way that the love letter could be transformed into a break up letter, but, as we saw, there were multiple ways!
Before entering the course two weeks ago, I really wouldn’t have guessed the significance of proper grammar and punctuation, but I have already discovered that it is crucial and really can change the meaning of what you are trying to say simply by placing a comma here or there.
Question:
For my question, I’m not really sure if anyone would know it, but I forgot to ask it in class the other day. I was wondering how the change from the “old” way to the “new” way for apostrophes came about. From what I understand, it was relatively recent that the change came about, but how was it decided that the change was needed. For an example, how did we go from using Chris’s to Chris’? Right now, both ways are right, but in the near future Chris’ will be the proper way to show a possessive form of an apostrophe. So, how did this change come about?