Agree Dylan - was about to make a post about this yesterday, but thought I was just "nit-picking" instead of giving anything
Two things has stroke me in this thread.
Not sure we are all discussing the same thing...
As one thing is to learn to boarddrag at first - another, VERY different is to learn to master marginal wind boarddragging
Alex, you show a picture where your kite is really low, when possible to drag like this it is really easy for any experienced hydrofoiler, and I understand you dont kick with your legs in this scenario.
But for absolute marginal winds, where you have to keep the kite very close to 12 o'clock, or maybe even fly it back and fourth a little to keep it in the air - it is a totally different concept, and using your legs to give more apparent wind and thrust, will help hugely - there is a reason why Gunnar (and I) do this, no matter if a foil kite or a light tube or a heavier tube - it helps.
I can not see why it should be better to drag out, than to walk out ?
Even with a 100 cm mast you can walk out a bit further than 100 cm depth
And in marginal winds, even with current, it is much faster and easier than dragging out, not in doubt.
It is only for getting out in shallow water I do it too yes, and no problem no matter if mast on its side or straight down - you walk as far out as you can first, as this is WAY faster than any board drag in marginal winds
If one got an odd spot with big hidden rocks and similar, okay, it could be different and you might not be able to drag mast down, but this is most likely rare occasions.
Personal preference what one likes of course - but the ability from the foil to drag upwind is a bit higher with the mast straight down - but you lose some of the board keel effect so I think (also my experience) it goes even.
Remember, say a 100 cm mast 10 cm average chord equals 1000 cm2. The lift coefficient of a 9-11 % symmetrical profile is about 1.0.
For a front wing say an Eppler 205, it is around 1.1 (but with less drag yes)
Meaning the mast itself corresponds to a 900 cm2 wing in terms of lift, so I think it overall is almost identical in terms of lift with the board into the equation.
Which is probably the reason why there are so many different ways we use, as they are pretty equal in terms of getting upwind
If loads of seaweed growing on the bottom, I prefer to keep the mast horizontal, if not, I keep it vertical as a lot more relaxed and can focus on working the kite.
In more wind, or with a super light kite, where you can keep it "lower", you can drag out quite comfortably yes, so these are two very different situations.