Which foot to put forward when coasting or track-standing? I am mostly concerned about track-stand here, because it requires much balance, so the question on "which foot to put forward" seems important enough.

This tutorial says "stand up with your strong foot on the forward pedal" (at time 0:46).

This tutorial says "the lead foot, which is the foot you're most comfortable putting in front..."

This strikes me very odd, because my right foot is stronger, but i feel much more comfortable with the left foot in front. When i am standing on my pedals, i mostly stand with my center of gravity behind the point where the cranks are attached. So it makes sense that my weight is mostly on the back foot, and it should be the stronger foot. However, other stuff i found in the Internet (example) invariably recommends putting your "strong", "good" or "dominant" foot in front.

What am i missing here?

Did i get used to a wrong technique, and should break my bad habits now?

Or is it not important enough, and i worry too much?
Just trackstanding on a flat road, mountain bike or other regular situation, just use the foot you feel most comfortable with in the forward position. The real key to performing a good, solid trackstand is to find a balance of forward pressure with your front pedal and resistance with either your brakes or your rear pedal (if you're riding fixed gear).

Another key to help out that I've found particularly useful is to try to keep the balance of the bike so that you can turn your handlebars in the same direction as your lead foot. This helps equalize the forward/backward pressures. Additionally, it helps prevent a tumble due to toe overlap, which isn't as big a deal on mountain bikes as it is on track bikes and road bikes because the front wheel is further out in front of the bike.

If you're trackstanding on an actual track in track racing - like a match sprint race - you'll want to have your right foot forward and turn your bars to the right. This allows you to use the banking of the track as your reverse resistance and your lead (right) foot as your forward pressure. Doing the opposite will make it much harder to control as gravity will want to pull you down to the middle of the track.

This same school of thought can be applied to a hill or other grade when mountain biking.