From what I've seen from doing Synergy is that you want to align all the needed elemental values to the correct state as close as possible to get a better chance to HQ.
Basically, you need to have them aligned perfectly for an increased chance to HQ. There is one exception though, you can have one element off by 1 and still have a "perfectly formed" Synergy.
From what I've seen, this increases your chances to HQ by a good amount. To view this you click "View furnace readings" and if it says "The synergy image has been perfectly formed" then you should end it right away!
Here's an example of what it looks like: