Guys, Need Clarification on Flash & html website

[Spark]

As mention above,

understand that having a Flash for your website will be a no-no for search engine.. But does it really that important till the extend that we can't have a flash template for our site and rank highly among the search engine?

As i am looking at webpage [Wordpress, html, etc] I actually do notice that some of the blogs that rank highly in certain keywords doesn't really have any keywords on their site.

Yes, i understand that it's important for on-site optimization. But from what i understand [unless i am wrong] the main part to get your site rank high is Off-Site optimization which your main page doesn't really play a big part. Ok, perhaps we have to work more extra hard than a normal Blog / html web page? but i don't see any reason that we need to work extra hard to get it rank high.

So what's the main reason why it's a no-no if you intend to get highly search for search engine. Anyone care to help?

Appreciate it. Thanks!

Regards,
Spark