I just want to add that an excellent condition is always followed by a poor condition, so while it is tempting to use a touch when the condition is excellent, there are drawbacks:

The chance for a failed touch is significantly greater on excellent condition, than even on a good condition - Excellent should always be considered a gamble. Whilst Excellent WILL result in a huge leap in quality, you definitely need to use it when steady hand is up, and I would even go so far to say don't even bother using a touch unless you know you would get 100% without it regardless. If I get Excellent early in the craft, usually I just hit observe. If I'm really desperate for the HQ I might sometimes take the gamble, but bear in mind that depending on the complexity of the recipe, a failed touch might screw it up completely.