Sorry but you didn't read my original post.
In any game where the players agree it's boring to sit and watch one player do a solo scouting round, assassinate is nearly worthless.
There simply will almost never be any surprise when a full plate character comes along.
Basing the Rogue design on the assumption that the fighter players must stop playing in order to enable my abilities is bad.
This thread is about suggestions on how to make Rogues work for groups that like to play together.
Besides, scouting ahead on your own is inherently too dangerous in games with any degree of challenge. To justify the risk of getting ganged by all the monsters by yourself, the assassinate ability needed to have been much stronger, and much more reliable.