The elevator is used to maintain airspeed. With some gliders, a small change in elevator is required to maintain airspeed when the brakes are opened significantly more, but the essence is always elevator for airspeed, brakes for rate of descent.
I think that you will find that the elevator varies the flight path i.e. if your current flight path is giving you 80Kt and you want 100Kt then you will use the elevator to steepen the flight path so that the airspeed reaches 100Kt.
If the elvator is used to make the flight path steeper then thanks to gravity a secondary effect is that the airspeed will increase.
The airspeed acheived in a glider is a result of how steeply the aircraft is descending along the flight path less the drag which is a function of both airspeed and configuration.
Trying to point to where you want to go in a glider would lead to potential disaster
Of course it would because in the absence of an engine, the only force available to provide "thrust" is gravity. However, if there was no variation in the wind, the constant point would remain that - constant and if the aircraft is clean and at the best glide speed then by definition there is no way to move the constant point forward. One can however move that point closer by steepening the flight path.
So again there is two ways of looking at the same actions;
Do you use elevator to steepen the flight path and add drag to prevent a speed increase or do you add drag and use the elevator to steepen the flight path in order to maintain speed?
When it comes to engine failures, I can confirm that people who use point and power as a mind set during powered flight unually perform far better.
Why? - simply because if you ask a person to use the controls to keep a point constant in the window then as an unavoidable consequence if they can do that task then they have to be able to recognise when the constant point is moving or no longer coincides with the place they wish to travel towards.
They usually understand that airspeed is as result of the thrust / drag balance coupled with the flight path and obviously in the absence of an engine all they have is gravity to provide "thrust".
Regards,
DFC