Simple questions sometimes require long answers. Those answers usually start with "It depends..."
If you're using a quality bark, it usually requires soaking before potting up a plant. Orchiata is my bark of choice, and really needs to be soaked before use.
Does your potting medium contain anything besides bark? For example... peat, tree fern, charcoal, sphagnum moss, perlite (sponge rock), coconut husk chips, scoria, grow cubes, LECA, etc. Those additions will also require different watering techniques, and the amount of whatever is included also changes water retention. For example, I wouldn't use a half bark/half sphag mix and soak the pot unless it was something that liked constant moisture (bulbo, phrag, etc)
When I grew in a bark medium, I would tweak it with other additions depending on the requirements of the orchid. That means either adding something that retains more water (grow cube, sphag, etc) and if I wanted to water and let dry quickly then add something that doesn't retain a lot of water (scoria, LECA, perlite).
So depends on what the plant needs are, how often one wants to water, and also air flow. I wouldn't want to pour water through a potted Phrag planted in bark, then not water it again for several days. If I soaked it, I could maybe get by with not watering again for three or so days, in a really low humidity environment.
There are so many variables, including the particular plant's needs and how often one wants to water, that humidity wouldn't even cross my mind as a factor. First, know the plant's requirements, then know your time constraints and how much time you want to spend, then tweak your medium of choice to suit it.
The short answer is I've done it both ways, depending on the plant. Either will work, and I don't think humidity is much of a factor either way.