Believe me, if you do both, I can assure you that you wont be marked as black hat, don’t worry about it. I suggest that you do both, it will truly help you in the end.

However, if you need to chose one or the other, which do you think will attract more visitors? Clearly, it seems like your goal is to rank higher; but itsn’t the goal in the end to recieve more visitors?

If you have an outside blog, how many people will see it? Will it do anything for you? Will you market that blog? If so, how?

How many people are currently looking at your website? Will a blog on your website help retain visitors and help sell your company from there?

Depending on the search engine, there’s far more to SEO than just links; inbound & external. It’s also how many clicks on the page once visited, how long vistitors stay on the page, and so on.

Inwhich case, having both will help trumendously!
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