So I work in a hospital (since 1988) and when someone comes in and we suspect cancer we just put them on chemo and radiation therapy. We don't do any tests to confirm cancer, we just start treatment(chemo,radiation).
So I see what you did there, Imagine now that we are not talking about cancer but something more along the lines of sayyyyyy PARVO (cancer is not contagious like ICH, Marine Velvet, Parasites, etc.) and instead of treating for it we just drop a carrier dog in a yard with a few hundred other dogs and see how it goes. Well, it wipes out the entire population within a couple days....I'm sure the actual loss is not a big deal because we elected not to put the last pup through the stress of treatment and all the other puppies where fine when we previously put them in the yard. Besides, he made it through the initial observation period with out any signs of illness and there was no reason to treat for anything ...Makes complete sense right? Look I'm not knocking anyones particular process for whatever THEY chose to do. I however choose the QT and treat absolutely everything I put into my tank because I have had several complete disasters over the last 2 decades of my own experience.
For the record I work in a Prison. We, as well as the population are required to be treated for certain communicable (and often ICH-like) contagious diseases BECAUSE in the confines of the environment we live and work in if we elect to not do so the rate of which disease spreads is faster than can be controlled. If I even come in contact with bodily fluids of an Inmate I am taken to the hospital and treated with a "cocktail" and QT'd from my family for several days to several weeks. Not because I I know what I Will contract but because of what CAN I Contract! I feel like the confines or our tanks are at the very least relatively similar.