Since I'm apparently in a debunking mood...
The differences between Tennessee Whiskey and Bourbon Whiskey are similar to the differences between "whiskey" and "whisky," in that there is much less to both of those dichotomies than most people think.
I recently revisited the whiskey/whisky thing here and here.
Similarly, people will sometimes get all high-and-mighty about how Jack Daniel's isn't a bourbon, and it isn't, but as a practical matter the difference is merely technical. For all intents and purposes, Jack Daniel's and George Dickel are bourbon in all but name. If they taste different, it is because each maker crafts a slightly different flavor. Those differences in flavor have nothing to do with them being a different type.
The primary effect of the charcoal filtering process used in Tennessee is to jump-start the aging process. Many bourbon makers say it removes too much flavor, but that is inside baseball. It is fair to debate that point, but it is still a very small difference. Tennessee Whiskey is very much within the profile of Straight Bourbon Whiskey. As far as the whiskey in the bottle goes, there is no practical difference.
The fact that both Jack and George have very little rye in their mash bills probably has more to do with their similarity than the Lincoln County Process does, and the fact that modern Dickel was created in imitation of Jack has more to do with their similarity than does their type designation.
It is also similar to the whiskey/whisky delineation because it is one of those essentially trivial issues that ignorant people pontificate about and newbies agonize about unnecessarily. Whiskey/whisky is two different spellings of the same word. I say you're welcome to pick one and stick with it. Likewise, "bourbon whiskey" versus "Tennessee whiskey" is a distinction without a difference.
Also like the spelling issue, the Tennessee/Bourbon thing creates myths, some quite persistent, about what the real differences are. Many people think whiskey and whisky are two different words, not just different spellings of the same word. Likewise you hear all sort of rumors, usually about Daniel's and almost always false, based on the fact that the whiskey isn't bourbon. It also leads to people assuming that bourbon must be made in Kentucky, also false.
I am one of those people who believes that Jack and George could be labeled "straight bourbon" if they wanted to be. Reasonable people can disagree about this, but that is how I interpret the regulations. You're welcome to have an opinion, but an acquaintance with the facts might be helpful in formulating it. Just a suggestion.
As you will discover, "straight bourbon whiskey" has a lot of requirements under the law. Jack and George meet every single one of them. "Tennessee whiskey" has no requirements, except the very limited ones to merely use the term "whiskey." So, in that sense, the regs are irrelevant.
A lot of people make assumptions about why Dickel and Daniel's aren't labeled as bourbon and all of those assumptions are wrong. They aren't labeled as bourbon because they choose not to be. There are other terms about which the same thing is true, such as Kentucky whiskey, Alabama whiskey, and Small Batch whiskey. The regs are silent as to all but the term "whiskey."
Conecuh Ridge, by the way, is careful not to use the term "Alabama whiskey," even though it is Alabama's official state spirit. That's because it is made in Kentucky.