Since the book isn't too specific on the ins and outs of what a pledge can give you, I've added some clarifications. Most of these are guidelines and can be flexible in the right situations.
The elements of the Task, Boon, and Sanction aspects should not exceed each other in power. A Medial Task allows Lesser and Medial Boons and Sanctions, but a Greater Boon should be left out unless a Greater Task is added. This applies to combinations of elements as well:
Generally speaking, two lesser aspects combine to form
a medial aspect. Likewise, a lesser and a medial aspect, or
two medial aspects combine to form a greater aspect.
-- Changeling: The Lost 176
The Adroitness boon is a bit ambiguous by book. These rules clarify its limits.
Stacking Adroitness boons within a pledge is fine, up to a max of +5 to any one skill.
It's totally OK to have multiple pledges whose Adroitness boons all boost the same skill. Don't go past a total of +5.
Adroitness boons grant you bonus dice whenever you use a skill, but they do not increase your actual rank in that skill. One important implication of this is that you cannot use Adroitness boons to satisfy merit prerequisites.
pronounced "pish-OH-g" [pɪˈʃoʊɡ]
Though it is normally used to punish someone using your own contracts, the pishogou sanction only says that a contract enacted at pledge creation immediately affects whoever breaks the pledge. By the simplest reading, someone could add a pishogue sanction to cast Hearth 2 to bless whoever breaks the pledge.
While this does work, the beneficial effect must be an actual punishment in the circumstances. Otherwise, the pledge does not work.