I think a great many of us use visual supports in every day life. Calendars, diaries, to-do lists, post-it notes etc, sticky labels on cupboards, colour-coded files, flashcards, reminders on PDA's etc.
Long before I ever became a Speech therapist, I always found organising and reorganising information in interesting visual ways (colour coding/different fonts etc/importing pics) was a good way of revising information I was trying to learn. I was very good at it - and excelled at remembering things academically. On the other hand, I was rubbish at using systems and visuals etc for organising and prioritising work. I never really did any of this, I relied on just memorising and remembering what needed to be done. Unfortunately, this never worked so well as a strategy for me and often led to me forgetting to do very important things, and suffering negative consequences for this.
I don't fully understand the resistance to using visuals in learning and even less so as an "aide de memoire" for organising oneself/structuring tasks. I still make the mistake of thinking I will remember things I have heard because of my good auditory memory, and don't write them down or use a visual system to back it up. This still causes problems for me. When it comes to using visuals to organise yourself or remember things that you are otherwise likely to forget, if it helps and you can use it independently, then it helps. I don't see it as "second best". If an NT adult can use all of these supports without stigma, then it concerns me when it is discounted out of hand because it's seen as lowering standards for kids with SN.
There are certain visual supports, like reminders of ways to do things, that may not be faded but it doesn't do much harm e.g think of the 6 steps of effective handwashing that you see in toilets - these are an ongoing reminder of steps that people tend to forget. A child's visual steps of handwashing could evolve, over time, to these more adult steps.
Would a behavioural programme be more effective in this instance? Well, yes, probably.. but it doesn't mean that following a visual schedule isn't going to get your hands clean iyswim. It also doesn't mean that your mind is going to waste away because you haven't learned this in a different way. I am not going to fade my diary or my Blackberry from my life, yet this isn't much of a problem.
My students with HFA are very capable of talking about which strategies help them remember and some students do tell us they favour visual formats of learning. Adding visual support to primarily auditory lesson content supports them in learning and remembering - they tell us this, they say it is easier to remember. I personally suspect that actually, adding visuals helps most students. School is a weird place to be. You have to spend five full hours a day just listening to people talking to you in a way in which, as an adult, you would have more ability to interact and take part. Sometimes a bit of visual input just varies things a bit, breaks it down into chunks, gives you something to hang on to. In and of itself, it may not be The Answer, but it is a support for people who are struggling in a wholly verbal environment.