Stating what your character does and how the other character reacts or is effected, is being assumptive and dictates Roleplay rather than let it go to it's inevitable conclusion.
For Example:
Player 1: Talia runs across the room and plants her dagger in Eric's stomach.
Or:
Player 2: Eric takes Talia's hand in his.
Both of these comments when written during a roleplay assumes the movement will succeed. The first, albeit more dramatic and character destructive, leaves no response as to what Eric would have done to stave off the attack. The second also assumes that Talia will not stand up before he has the opportunity to take her hand, or perhaps turn away.
To interactively work out the process it would look like this:
Player 1: Talia runs across the room, dagger in hand, an attempt to strike at Eric.
Player 2: Eric stands there, stunned with disbelief.
Player 1: Talia lunges for eric's midsection.
Player 2: Eric's eyes widen, hardly registering the pain as his own. He watches as if in slow motion as the dagger plunges into his belly.
The end result was the same, however the manner it was reached was different. It was a cooperative, interactive, process. Allowing the defender to react and decide if the character would be too shocked and stunned to move or if he would immediately react and try to side step. The last sentence could easily have read:
Eric attempts to move to the side.
Note the use of the word attempt, again we do not know if he will suceed in his action or not. That will only be determined by circumstances, character abilities, and other information that is contained in the roleplay leading up to this point.
Another, more daily example:
Player 1: Eric moves to take Talia's hand.
Player 2: Talia smiles at the gesture, but squeezes his hand lightly then rises from her chair.
Player 1: Eric looks up at Talia with a questioning look
Not the same result as the assumptive statement. The interactive process showed that Talia had something very different on her mind.
The difficulties in working in a freestyle environment are that we must recognize the strengths and weaknesses of our characters. If Talia were trying to fight Eric with a lightsaber, Eric is going to win, he has years of training on Talia and it would be unrealistic of me to expect her to win unless other circumstances were in affect. Such as Eric being wounded and sleep deprived or totally taken by surprise. Or if Eric had multiple attackers besides Talia.
These are all factors that must be taken into consideration when roleplaying in a diceless, statless, freeform environment.