I actually tried elevators in earlier versions of thunderclap, but I didn't like how they don't provide constant elevation (you have to wait for it to come down).
So yes, I speak from experience. I offer two suggestions if you wish to keep the mechanic.
1) Use an elevator that is activated by the player. No one wants to come running to a lift, on fire, to see that they've missed it by a few seconds.
2) Use a 'lift'. This is to say use a trigger_push to push the player up instead of using a func_door to act as an elevator. This is currently what I use because anyone can use it at any time. The only requirement is that the player has to fall into the trigger, or jump into it in order for it to lift them.
Finally, if you are willing to ditch the mechanic, I would suggest changing your layout to accommodate some stairs or ramps instead. I only suggest this because of the ensuing confusion of lifts/elevators that aren't properly explained to the player.
And just because Valve does something doesn't mean it's right
Don't use elevators.
Need for elevators indicates a bad map layout.
I disagree, I think need for elevators is either intentional, or indicative of a mistake when calculating travel between height variations.