@Syv, I didn't say the dyn bonus was bad in the current system. Quite the opposite, though saying that the bonus is good is entirely different from saying that the bonus is a perfect game mechanic. (it isn't)
I also agree with you that it is quite necessary in the *current* system.
My point was that in the proposed system, it can be easily replaced by a more active choice that doesn't cause players to waste time just so they can insure themselves against failure. They can choose to shoot the thing, and have that simple action be (relatively) safe. Or they could push it, go for broke, and risk greater penalties for failure. This is a much more interesting choice to make, rather than choosing whether or not to do nothing. Similarly, they could choose to perform an action carefully, as a modifier on the difficulty of the action. This could decrease progress rate and the side effects of a crit fail or overshoot. All of this choice in preparation, without having to spend a turn doing nothing. When your player is voluntarily doing nothing for any reason, there is a problem. Games live and die on action, so giving a bonus for inaction is a very bad idea.
And if you're worried about the system being abusable... Well, Nyras has a bat for dealing with these problems.
(( Also, since you hinged on it when it's besides the point, I'm using the word 'star' incorrectly here. One of the most common overshoot states of our pyro amps has been a massive heatup of an area, causing an explosion and usually destroying anything nearby. I usually call it a 'star', due to the cause of the explosion. It's the instant addition of high heat, which violently dissipates into the surrounding area. ))