[wpietri]

His point, with which I still agree, is that running a business is different than starting a business.

More specifically, running a business with a known, stable business model is a very different activity than starting from scratch and discovering a new business. MBAs prepare you for the former, but generally not the latter.

A point that your history seems to match: you started and ran a business just fine without an MBA. And now that you have one, you've turned from entrepreneurship to working at large company.

[bahman2000]

There are MBA programs that are specifically tailored for entrepreneurship, such as the Babson College program (disclaimer: I am an alum).

For instance, there are specific tools and frameworks that, when used properly, help you identify the opportunities worth pursuing.

Further, you can be an entrepreneur in both cases: when starting your own business, or working for a large company. It's true the other way too: you can start/have your own business and that wouldn't make you an entrepreneur.