Here you go sir, a three course meal:
1)As for whether you should retake the GMAT, I'll repost something I wrote our friend kingkong a few days ago:
s for advice on whether you should take it again, I've posted this before a bit, but it depends on a few things:
a) how old you are (i.e. Would being one year older harm your chances?)
b) your real life situation (i.e. is this the perfect time for you to go because you just got married, or can you reasonably stay on because you will get a promotion anyway)
c) how much under your potential high score you are scoring
d) how close we are to deadlines.
In your case it's a bit different because here 20 points WILL make a difference (30 will make more and 50 even more). Because 680 is just scraping the low end of the mid 80% of admits, so unless you are a Minister's son or something like that, you might have a tough time of it. And you are talking about two of the top five programs there are.
To answer question2: It'll be tough unless you have some pocket rockets (i.e. you founded a million dollar company, your father owns a huge family business, etc.)
3) HBS does like legacies! That is true. But they also like high GMATS
. Luckily you come from a good industry, have expereince in oil and gas (although I think you can tweak your goals somewhat to make them stronger)
Hope this helps!
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