I like to keep from walking too close to eht edge and filtering seems very easy to do that. One point to the filter is that we never want to do things which totally disrupt the bacteria and having bacteria in a filter is one way to have some added safety.
What can happen if you only have bacteria in the tank and none in the filter and you decide to do a really good cleaning of the sub and scrub down the walls? You can be running very close to an ammonia spike! But you can get away with doing a couple foolish things if you hedge your bet and have some bacteria in the tank and some in the filter. In that case, you only have to remember to NOT clean both at the same time!
Keep a little slack in your operation as I have found I WILL screw it up at times!
Human is to error once in a while, smarter human assumes it will happen and prepares for it!