it should be normal that you have a lot of rewrite rules to your site. As the site gets bigger the amount of pages you need to rewrite grows, and depending on what the pages do, you could have multiple rewrites per page. This is all based on how secure you are making your site. More security means more precautions.
module gives you the ability to transparently redirect one URL to another, without the user’s knowledge. This opens up all sorts of possibilities, from simply redirecting old URLs to new addresses, to cleaning up the ‘dirty’ URLs coming from a poor publishing system — giving you URLs that are friendlier to both readers and search engines.
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so pretty much it's at your discretion. How secure do you want it to be.