This was the OP first post. Some of us has answered that WC is a tool like others but should be used only when is needed - not as a routine. Some of us has answered that´s it the most important tool in order to hinder "stuff" building up. What "stuff" means is rather unclear - it seems to vary a lot. But the general idea is that if you do not take away "stuff" - your tank will crash in the future. To do WC as a routine is the most common advise I see in here - still I read a lot of things about tank crashes and other things like algae problems. For me - doing regular WC is one way of reefing - but the holy graal - its not.
Other argue that they never seen any successful non routine WC tanks of age more than 2 years. To be honest - I doubt that the survival time for the average tank (with a routine for WC) is more that that

Despite the use of WC - a crash sometimes happens anyway.
The last pages the thread is about the few promille who want a specialized high end coral aquarium with species that are hard to keep. It is impossible without regular WC - some says . I think that the picture invasion from Dutch aquariums have proven even that statement wrong
This with adding stuff. No one can argue against the fact that regular WC will expose a risk of adding impurities to the water. The general idea is further that this impurities will build up in the aquaria and in the end show up in the water column. My experiences is mostly the opposite - most compounds will be blocked in gravel and/or incorporated into biomass if they are not put into the aquarium on a routine based pathway.
IMO - if you run a NWC based regime - there is a couple of things that can improve the result. One is ICP testing - not cheap but a very useful tool. The other thing that is important for me is the food. I prefer natural, frozen food like adult artemia and copepods. I do not use dry food. IMO - normal dry food for fishes can be a agent for too high levels of zink in the water column as an example. I have notice that zink levels tends to build up in the water column of a total closed fish farm I work with.
@Matthew Morrison - I think that this thread has give you some ideas of the reason why people advocating routine WC. And also the contra arguments for this routine. Now it is up to you to chose pathway for your tank
Sincerely Lasse