Unused components ?

I saw in some filter that there are components that aren't connected with anything else. They should not influence the filter in any way. Am I wrong? I tried to delete some and I saw no difference in the filter.

Thanks CFandM.
I generally saw only 1 component unused, so it is not hard to understand that it was probably simply forgotten.
But when we are in the beginning, there is always the doubt that we may misunderstand something in how the program works. So I thought to ask.

I also noticed that in few cases a group of components is repeated two times in the same filter.
I make an example. Let's suppose that I have:
"Image" connected to "Profile gradient" and "Blur", that are both connected with a "Blend".
If I need to have this same effect in two different areas of the filter, I could set two connections from "Blend" and it should be ok.
Instead in some filter I found that the maker repeated the same "Image + profile gradient + blur + blend" two times. Then he applied them with a single connection each to the two parts where they were needed.
Is there any reason why repeating that same group of components should be preferable than making a double connection from one single group?
If the settings of one group were different ( for example a different color in the "profile gradient" ), then I would understand. But if they are exactly the same... does it make any sense?
( It was not in one of your filters. )

Yep just as Craig said...You can use that one part of the filter tree and branch out to the other areas of the filter that require the same routine...
There are some instances however that work better with duplicate components rather then just connecting one to different spots...Offsets are in this category....When working on the anaglyph filters one can see that I repeated the the rgb extraction and offset group many times with no change to anything...I could have connected the offsets together but it gave a different result and depth was horrible. So repeating the same components was the only way to get satifactory depth from the filter...
So its sometimes also on a filter by filter basis...Whats best for the filter as far as the look you are going for and what is the fastest..

and welcome to FF, Ramlyn

i'll make one last note here for on all this. right click over the 'results' component and select the idea in the little menu that pops up, 'select sub-tree'. this will highlight ALL the components that are actually attached to the results component. you can then just move the whole group and see if there are any orphans left behind that need cleaning up. this will work on any component, btw, but it will only show those components earlier plus the one you right click on. so, it's also a good way to find just what's in one leg of a filter when trying to figure what the heck it's doing