It's a shame more people don't fly gliders before they (progress?) to power. All the same issues are there and others besides! Due to the nature of soaring, you learn from an early stage to feel for the stall, to fly as slowly as possible even in a very tight turns (to remain in the core of a thermal). Great emphasis is placed on stalls and SPINNING! for reasons of high exposure to the risk. Gliders with their greater wingspan, winch launching and thermalling activities are often flown within a wasps breath of the stall. ASI is important, but it's only feel, attitude and experience (by practice, not hours) that keep it so safe.
I've mostly flown small underpowered PFA types, with dubious ASI's (and sometimes strange flying characteristics) so I've learned to use airspeed as a guide rather than as a dictate. I'm not suggesting everyone ignor their ASI, but I would encourage them to remember attitude, power settings ect for a given airspeed whilst everything is working fine. Then when the day comes (which it will) when a problem occurs, they will be prepared and will automatically fly by instinct and not by numbers. Or course, when near the ground the ASI is invaluble as it's easy to be suckered by wind affects on visual clues ... but if well trained and aware it is still not essential.
I noticed someone mentioned only doing shallow turns onto final. That's great, but don't fall into the trap that of thinking shallow turns are always safe. It's too easy to worry about banking and then feed in more and more rudder to stop from overshooting the centre line. A low, slow skidding turn is a real spin scenario! Banking is fine if properly co-ordinated and the correct attitude (or if you prefer ... airspeed) maintained.
"Seat of the pants" sounds very Gung-Ho and old school, but in reality anyone who has learned to fly, will (even if they don't admit it) fly by visual and sensual clues. The trick is to know when to ignor them!
SS