Also i have been checking how the respawn times are scaled by players. im not 100% sure but from reading i was able to probably find out how it works:
TF2 Blog said:
How do respawn waves work? Is my respawn time affected by my performance? Why do they exist at all?
Respawn waves occur on regular intervals, based on the map settings. Most of our maps use a 10 second respawn wave time. That 10 seconds is then modified by the map state, generally reduced for the team that controls the most capture points. Each team's respawn wave time is then scaled down if the team has less than 8 players in it, to a minimum of 5 seconds if team has 3 or less players in it. When you die, you are assigned to the respawn wave after the next one. So if the respawn wave time is currently 10 seconds for your team, you'll respawn somewhere between 10 and 20 seconds from your death. Your individual performance doesn't affect your respawn time in any way.
From that bold part i think any ammount of players above 8 have the normal respawn time unscaled. However, below that count it reduces at a linear rate with the minimum on 3.
So to give a more clear example of what i mean:
at 8 players its 10 seconds. then for each less player that time is reduced with 10%
7 = 9
6=8
and so on until
3=5 (which is 50% of the base time)
And if the respawn times would be 20 seconds then at 3 players its 10.
Also, from those wiki pages you updated:
However, unless the server population is low, you will most likely have to wait for the wave after.
You ALLWAYS get in the respawn wave after the first one. And this explains why in map testing you allways see double the respawn time. You die... the timer counts from 5 for the next wave. As you arent in that one youll have to wait another 5. It doesnt care that a wave is empty.