Since the validity of the radiometric dating is not under contention by the vast majority of the physicists and geologists, bringing up what opponents consider "assumptions" in the process would be a bit unwieldy. Additionally, if I brought up all the "assumptions" that I have heard from opponents to an old Earth, I might miss one or two. That would make it appear that I were trying to hide something. Instead, I offer to address any objections that you have. It is likely that I might learn something from the exchange.

Perhaps it wouldn't be dishonest to make that assumption and admit to it. However, I know that is not how the curve shape was determined, so it would be dishonest of me to say that they simply assumed a shape.
Additionally, your characterization of the "stacking up" of assumptions strongly implies that scientists simply make up assumptions out of thin air. I have shown that this is not the case with the exponential shape of the decay curve. Drawing conclusions from one assumption is not stacking up assumptions.

Do you mean different decay rates for the same isotope or different decay rates for different isotopes? This looks like a good subject to go in depth with because I have not seen the "circular reasoning" argument before with regards to the conclusion that decay rates are constant.

Well, when my mentor has pointed out unChristian behavior by me, I don't look at it as "trying to make me feel guilty", although I tend to. Yes, I was trying to influence your behavior by pointing out where you seem to act contrary to your stated belief system. Was that right of me? Probably not in the sarcastic way that I did it. I am not your mentor.

In this debate, we disagree to a large extent. I think you are honestly trying to support the truth as you see it. I am doing the same. I am not scientist and, it seems that neither are you. We are both going to get frustrated with each other for "not getting it" when we think the point should be obvious.

At some time during discussions each of us has and is going to try to make a point quickly, easily and not very well in order to score something against the other. So we use a turn of phrase that undermines the others' position rather than using data to do it. Rhetoric rather than evidence.

I think that will happen regardless of the fact that we both recognize that it is a possibility.

Romans 7:19...For what I do is not the good I want to do; no, the evil I do not want to do—this I keep on doing. (NIV)