I disagree, methods of administration and the spacing and size of your doses of substances cause different pharmacokinetics and therefore different peak plasma levels. Norketamine is a metabolite that I believe does much harm and that harm may increase exponentially when blood plasma reach higher values, you can probably consider it like internal organs have a threshold to tolerate stuff like this before it becomes a problem. Excess is a function of toxicity right?
The cytochromes are microsomal hepatic enzymes that are responsible for the conversion of ketamine into norketamine. Shambles didn't mention that but I did because I think it
might be relevant to the equation.
Shambles did indeed say that smaller lines over time may be less harmful and less wasteful (read his equation). Of course we are comparing equal total amounts of ketamine for it to be a fair comparison.
So, what is different about the smaller lines over time? The peak plasma levels of ketamine itself and the metabolite, are factor nr 1.
What I was saying is that another factor that determines the levels of the metabolite is enzyme saturation. At some point - if one did big lines - ketamine could be like 'standing in line' to be converted meaning that you have high ketamine blood levels but topped off norketamine levels, which sounds to me like a win. The question is how fast this saturation is reached, it seems the harmful high peak plasma norketamine is a much stronger factor than enzyme saturation (if that happens at all) so I'm probably wrong.
Another thing is that big lines are wasteful because a lot of it turns to drip, which is absorbed orally getting you less bang for buck but lots of norketamine from FP metabolism. I heard that you can only take like 75 mg per nostril per 10 minutes, practically, the rest is expelled to the throat. I think its an entirely believeable value, especially when the K is not 100 pure. Impurities that are not easily absorbed by the nasal mucosa could deter correct absorption.
Hopefully that clears up what is opposite about my suggestion but I do believe that I'm wrong about the enzyme factor, so I think the rest of what I said explains roShambo's logic.

Correct me if I'm wrong of course.
But as you can see there is definitely more to it than personal preference!