Thanks for the advice. I plan on learning more and more about light, flash, composition, etc. i have made great strides in the short two years I have had a dslr. I do realize that phtography lessons are needed but i figured they woukd be better practiced on this than having to learn methods and apply them to a different body later. I will still play with this a week or so longer and decide if the investment is worth it now or in a year or so when I have gained more skill. Did you think the photo's turned out ok?
From your statement it appears that you are not a professional photographer (I mean only that you probably do not earn anything substantial from photography yet) and you are learning and enjoying your photography technique. My understanding is that your 60D is a good enough camera (probably more than good enough) to do that. You have stated that you think it does not make sense to learn techniques on one camera body and then apply them with another camera body. Well it is not as if you are changing from Canon to Nikon to Sony where the lay out of buttons and menus makes the cross application of techniques time consuming. You are learning (or going to learn) techniques on a 60D which is more or less functionally similar (definitely not identical) to all other DSLRS of Canon lineup. Moreover, there is another issue to consider. Do you think you shall be satisfied with your 5DIII in 3 years/4 years down the line when 5DIV or something like that comes up? Then you will change to 5DIV and that will be a new body. You WILL have to "apply to a different body later" one way or the other. That is probably not a very sound rationale for buying 5DIII (you definitely may have other reasons to buy 5DIII, I am just saying this particular logic is not sound).
Ask yourself, if you do not see the difference between 60D photos and 5DIII photos then why buy 5DIII? Just because it is a "better" camera? But how would you enjoy its "betterness" if you yourself are not sure in what way it is better? Instead of buying 5DIII today you can invest in better lens/glass and two years from now when your 60D grow long in the tooth, you will definitely have developed so much as a photographer that you will probably buy 5DIV (may be or something even better) and enjoy it better. Because you WILL know "how" that is better than your old 60D or even the current 5DIII.
My 2 cents.