04/07/2015
Today, I saw a post and after reading, I was incline to answer. Part of the question/post "Each of the testing sites that I have been using give me conflicting error information. I am asking are others in the same boat recreating a second mobile site or using css style for handheld. There is no time to do a full reactive site due to other stuff. I just want to make sure that the good rankings for this site do not falter."
My response is:
I do similar testing; W3C http://validator.w3.org/ and there are three options on this website on how to perform the test. The three options are Validate by URI, Validate By File Upload, and Validate by Direct Input. I rarely use the first option, the 2nd option wouldn't work for me for most case (PHP), and the third option is what I use primarily.
The best way to perform this test is to first view the site in any web browsers, after you view the page you would like to test, look for the source code. (Chrome, View->Developer->View Source). This will show you in plan text the code of the page you are viewing. By doing this, this eliminate any PHP. With this source code, I would copy the cods from the browser, open W3C’s website, click on “Validate by Direct Input” and past the source code to perform the test.
Your last question; my version, Should you use one html and style for both desktop and mobile, or to create a desktop version and mobile version of the html and style these two in numbers of ways. The answer is both are viable option. For the most part, I would stick with one html and style it to be responsive base on the device that is to view the site. This is completely done with CSS. The other option is usually picked when the site is more complex with server-side scripting language involved. To clear any misunderstanding about scripting language, just because a site has server-side scripting language doesn’t make it complex.
I hope this help, I would do some research in Responsive CSS and CSS3 Media Queries.