The Duetto v3 comes with 4 different steam tips. 2 hole, 3 hole, and two 4 holes with different layouts.

Prior to the Duetto I had a Gaggia Classic with 1 hole and got good with it. Now that I am dealing with multi holes there is a learning curve, not to mention the additional steam power. I had much difficulty with the 2 hole, but am doing pretty good with one of the 4 hole layouts.

To the question(s). What is the advantage/disadvantage of the additional holes on the tip? I understand in simple terms it moves the milk differently, but I guess I am looking for something more comprehensive.

Also, do you need to use a different technique for each style tip?

It's been a long time since college physics, but I think the math is similar (if not identical) to parallel electrical circuitry, where the total resistance to flow is not merely the sum of each resistor (wand tip hole in this case), but rather the inverse of the sum of each holes inverse...uh, no that's not exactly right, but look up the formula online and you'll get the idea.

Anyhow, in the practical world, yes, number of holes, size of holes and angle all matter. The pitcher size and shape matter too, as well as the starting pressure.

I know you're read the threads about doing the burn me conversion, but I don't know if you did it on yours. If not, and you don't want to, you might want to consider clipping the insert tube shorter. Jeff Cirelli "jmanespresso" reported similar results as those of us who've pulled the tube entirely. I was having a bear of a time in the beginning, having come from a Silvia, where not only was the wand on the other side of the machine, but of course, the pressure is totally different. I was like, wtf?, I couldn't steam worth a sh!t for like 3 months, and then when I pulled the tube, it was night and day immediately. After I got used to the 2-hole tip I gradually got more and more disappointed with lack of milk sweetness from the still long steaming time, and finally forced myself to get used to the 4-hole tip (I have a Duetto II and they only came with 2 tips).

It is my belief that every time you change something...whether it be machine, wand, tip, or pitcher...there's yet another learning curve (though, some of the curves are steeper than others). However, this is possibly not true for real pros.

As a general rule, the more holes, the faster the steaming and more turbulent the action in the milk. That is provided the machine has the power to sustain the pressure. The more holes, the faster the boiler energy will be depleted. If your heater does not have enough power, you can run out of steam quick.