If you use a dagger for ambush, yeah it might work. HOwever you wont hit your target much after that. I looked at all these rangers around and it makes me laugh seeing them with daggers and other such toys.
Dagger might be effective for succeeding that ambush but it wont be effective in landing the kill.

People stick with axes because axes provide just raw killing power. I only used staff when i had to ambush a svirf or gnome, maybe non giant APs as well since they cant parry it well.

In my experience with rangers i have not found any use for all the other ambushes, except onslaught and drive. I used drive to drive the tank away from the group while they were ranking on large guards, failed 6 of 8 times.