I had this idea for an experiment in another thread, but I thought I'd post the results here. I've been flying my Python Mk I, Elegence of Purpose, that has a capacity for 240 tons of cargo in its "multi-role" configuration.
Out of idle curiosity, I've been examining the difference between the "one ton" method, and the "bulk sale" method when it comes to selling high margin commodities. From a strictly "bore yourself to tears while minimizing any danger whatsever," the "one ton" method is clearly the way to go. I've found a commodity that lets me sell unlimited amounts at my destination for 36 merits a pop, which works out to be 8640 merits over the course of about thirty-five minutes. Plus another 180 merits if I bulk sell something on the way to pick up that commodity.
On the other hand, I can complete three and a half round trips during the same time frame, which give me a little over 700 merits per trip if I diversify my cargo, or about 2500 merits during the same amount of time. Not counting the the occasional ship scans, the opportunities to drop into PowerWreckage USSs I'm carrying some limpets for, or allowing a pirate to catch up so I can kill them for the bounty (plus merits). This is, quite frankly, a lot more than the alternative.
From a more tactical point of view, given that one of the eight commodities I traded along this route seems to way more profitable than it should be (based on a quick look at Inara), in most systems I'd be making about 2800 (+ 180) merits using the "one ton" method, which isn't that much more than an estimated 2400. Taking advantage of any opportunities along the way could easily exceed that quantity.
Plus it's a lot more fun, as well.
The weird thing is, margin had a much larger to play, when it comes to merit generation, than I expected. It seems that margin, profit, and sale price all have an important role to play. But when it comes to bulk transport, Power commodities still has everything else beat. If only there wasn't a time restriction on them...
I'm going to do some more testing, to see how things pan out.