So what's your point ? If today your response of "editing" is merely just trying to define its scope, then based on what is described in the wiki
http://en.wikipedia.org/wiki/Editing, I see editing totally supersede the process of adjusting colour. In either case, you either come around the topic that adjusting of colour is editing, or stick with your understanding and we stop it right here, because we are not in the same wavelength.
If you so happened to wanna understand what is Lightroom and what it is capable of, I will be more than glad to give you some workflows on how I use Lightroom and you find a way to fit that into your own workflow.
Before I indulge into what Lightroom has to offer, we discuss in a much bigger picture. Both Lightroom and Photoshop are high end raster or bitmap manipulation tools used by creative designers all over the world. From a business stand point, it is suicidal, if not nonsensical, to have 2 top end products cannibalize each other. It is damaging to profit and products classification. If you actually get this point, then there is nothing much to debate about and just accept the fact that these 2 products are targeting at 2 radically different groups of creative designers.
Lightroom has most of the workflow that are easy to use and very much right in your face when you deal with photographs. That being said, I won't limit it to photographs as the main contents to managed, art works such as graphic designs, illustration, fine arts are also good candidate for manipulation. Now lets just highlight some important aspect of Lightroom. On the left is a panel of folders, collections and tagging functionalities they are important when you are dealing with large number of photographs. When I just finish import a series of photographs in numbers of thousands, I want to quickly tag the photos to particular groups so that I can pick and trash photos of particular scene or genre. This is process is very hard in Photoshop. Photoshop main working area is specific to each photographs and not about handling in a large quantity. I want to also identify which photographs should be in a collection and which are not very quickly clicking on the top right colour of the small thumbnail by putting them in a smart collection which I can later convert into a named collection. Again this is not possible in Photoshop. I know that I have a series of photos that I have taken in the morning at the same location that need at least 2 f-stops up for their exposure because I unintentionally stop down for the exposure compensation in the camera, I can easily select all these photos and then apply the same exposure compensation in one go. Try doing that in Photoshop and you will be down to actions and batch processes, and how are you going to select those photos without a library management feature in Photoshop ? We do know there is a Bridge feature in CS, but that is not inside Photoshop, it is inside the Creative Suite. I also need to quickly crop photos and rotate them and adjust their perspective, and keystone and lens distortion in Lightroom. That is possible because that's how Lightroom is designed for such workflows. Try doing it in PS and you will be opening up several dialogs from different menus and eventually you got ONE pathetic photo done. That's indeed "fast" workflow huh ? 1 down and 999 more to go.
You see, if you actually used a Lightroom for some serious workflow and not less than 10 RAW photographs as your portfolio, I say you can stick with Photoshop. If you are a serious enthusiast or a photographer making money from almost daily shoots, you will highly recommend or cannot work without such ease of management and fast workflows.
At the end of the day, SMART is not applied on photographers that choose the one and only productivity tool, but one who uses the BEST tool for the RIGHT job. If you try to bend your ways around Photoshop and got it working, I wouldn't even applaud, but rather say you are plain stupid, because you could have used another better tool and save to 60% of the work and time.
If you are tight on budget and cannot afford both softwares together, and you have to choose one out of both, then you have to assess on what is your most frequent tasks in your work and decide which you want to save your time on. Because I'm a working individual, I see US$300 is a god damn cheap price to pay for if this is for business usage. Any bosses says that is expensive can either rethink your business model or don't be offended when your staffs call you stingy. Now US$700 for PS is indeed expensive for my level of assessment. Perhaps not 10 copies for a business but I say you need at least 1 copy for each full time designer that is going to make your photographs looks impressive at the end of the day.
In the industry I work in, industrial standard is the way to go. Not in the industrial standard set you back from the competitors, and sometimes out of the picture. Lightroom and Photoshop are both industrial standards. If you are a photographer, you will want to go this route not because it is cheaper, but because this is what others will expect of you when you even wanna start a conversation or process with them.
After this explanation, I hope you will wanna go and rethink on whether colour adjustment is editing or not.
But then Lightroom use only for adjusting the colour not editing.