Have you ever heard of the "table cell trick?"
It used to be that Google would only read the first 100KB of a web page. This was back when they didn't have hidden datacenters all over the world tucked away in type 1AAA shipping containers packed with 1,160 servers in each.
Yes, those statistics seem to be true. Although no one outside of Google knows how many servers Google actually has, it was last estimated in 2009 to be almost 1 million servers! It's our guess that they build their server "rooms" inside shipping containers so they can move them whenever needed (think disaster, war and acts of god).
The Google server room engineers have to think in terms of "cost per search." For them, they need to calculate the number of servers and electricity and payroll and all other possible factors it takes for each one of us to type "wedding rings" into google.com and get a fancy SERP back in under 1 tenth of a second. So to cut their costs down, they limited every page read to the first 100KB.
In August 2009, Google released one of their normal training videos, and although the video was about image licensing, they also revealed that they read all of a web page and not just the first 100KB.
The other thing they revealed in that video is that they "do a real good job" figuring out what the real content of a page is now, regardless how bad or disorganized the programming code is.
The table cell trick mentioned above was, and honestly still is, the preferred method to structure a website so your primary content appears as a chunk of readable information within the first 100KB of your page. This chunking separates your left/right navigation and the header/footer from what we call the meat of a web page. Advanced website programmers will use style sheets instead of table to accomplish the same type of chunking on fancy new websites.
What does all this mean to you? Simply that you don't have to worry too much anymore if your web programmer creates sloppy code. We still don't agree with sloppy disorganized code; it simply means you shouldn't worry so much about this anymore.
All the content of your web page is read and analyzed by Google. They look for the primary content and throw out the rest, including your navigation on the side. If you want Google to find every page on your website, you should put links within the primary content (meat) of your page.