Tuft said:
The big question with such freeform stunts have always been: What happens when they get close to the defined stunts, who may be restricted in some way: require purchase, have limits on usage, etc. Do you suddenly prohibit that particular freeform stunt because it duplicates something you otherwise have to pay for? In the above example, the table kick is awfully close to doing a Trip, which you (A) have to buy as a power, and (B) is limited to once per encounter.
And what happens when new splatbooks come out with new Powers? Will those further restrict the freeform stunts availabe to you?
It was definitely something that 3E seemed to be in risk off. I am not sure if 4E will be better in that regard. But here is my "guess":
Powers will always have a significant advantage over improvised maneuvers. They either deal damage plus the maneuver effect, or they take only a minor action or something like that.
At the same time, while powers are still "superior" for the most part, you don't suffer any penalties on your checks and rolls for your maneuver, and you don't provoke Opportunity Attacks (at least generally. I guess "throwing salt" might be a ranged attack, and might do it for that reason alone, but not just because you're performing a "stunt"). This means in those situations where the maneuver looks like a good idea since it's effect is useful, you have at least a fair probability of pulling it off.
So, if the Martial Sourcebook will contain a "throw salt into face"-power, it will only require a minor action and blind the foe until the beginning of your next turn, and usable once per encounter. After your minor attack, you can still run away or strike your opponent while he can't see, and on his turn, he has great trouble striking you since he's still fighting off the salt in his eyes.
If you want to do the same without the power, you take an attack action and get the same benefit. Since it's an attack, it considerably lacks its effectiveness, and instead of using it to beat your opponent up while he's blinded, you probably just run away and hide behind your friendly neighborhood defender...
3E didn't really have the mechanical "granularity" to pull this off, at least not until Swift Action where introduced, and Bo9S offered "encounter"-based powers. Touch Attacks, AC and Saves also didn't scale proportionally, making it harder to create a fair, unifying mechanic (or guideline) for improved maneuvers or stunts. The BOIM might tried its best in that regard, but the attack penalty and attack of opportunity parts often make it feel to risky (I get attacked and have a low chance of actually succeeding? I guess full attack it is, then...)