Dilution with No THC

Here's the deal: My two friends and I are about to be put on probation all together because we all got caught together (what we did is completely irrelevant to this thread, but I'll tell anyone that would like to know). We've already gone to take our first drug tests to establish the baseline. We really want to attempt dilution because substitution is pretty much out of the question with the P.O. breathing down our necks when we fill the cup. However, we want to do a dry run of dilution before actually partaking in any illegal activities. What I mean is that we haven't smoked yet but whenever we go in to take another drug test, we want to dilute our samples in the exact fashion (N2's method) that we would once we do start smoking (if we do) so we can see if they detect the dilution or not. This probably isn't the most 100% safe way to do it, but we figure that if we get away with diluting our sample once, then the next time we go in to do it, we can do it and be able to have success with THC in our systems. I know that getting away with diluting the sample one time does not mean it will succeed every subsequent time, but it at least increases the chances of future successes. My question is for those with any knowledge or experience of dilution, if we can get away with dilution if there is no THC in our systems, will we also pass the test with THC in our systems as long as they do not fail it negative-dilute. I know that I will not receive a direct answer because there is absolutely no way of anyone knowing whether or not this is possible for us, however, I am just looking for a response that responds to the theoretical "If I dilute my sample and get away with it without any THC in my system, then I can do it with THC in my system." Essentially, we are doing a dry run. Excuse the redundancy and the length but I wanted to be thorough so whoever attempts to give me a decent answer can do so with knowing everything about our situation. Thanks in advance for any help at all.

Why not do your own dry run? You could always check your efforts, using a validity test strip that checks the creatinine and specific gravity. Validity test strips can be had dirt cheap by doing a search for drug adulteration test kits on google.com..

That would be a good idea if I knew what the creatinine/specific gravity levels were that I had to reach at probation but I don't. That's why I want to just see if N2's dilution method will be undetectable to them.