[TheLastSuperman]

Yes I concur because I've seen a simple .htaccees edit bring down entire sites and anything dealing w/ the cache unless you know what it does do not include as it can cause issues... integrated sites for example those that use Wordpress and vBulletin... using the W3 Cache Plugin for wordpress in a situation where it's been integrated can cause issues among other things. Also it's not well advised to have a huuuuuge .htaccess file either, just a heads up .

Be very very careful about "Optimizing" your site by yourself, if your not careful (experienced or not) you can actually mess something up.

Edit: Also if your ever in doubt, rename .htaccess and then check the site, if your using vBSEO then yes it will seem funky but for example if you edited your .htaccess then uploaded and noticed after refreshing the forums style was all white w/ blue links and no images or backgrounds... well there's your sign it was the edit you just included in .htaccess so now undo that edit and re-upload and your back in business!