Power

Power measures the potential which one Champion possesses to apply pressure to an enemy champion or objective. It is a combination of the potential for damage, crowd control and other utility (eg. heals) a Champion can output over a defined period of time. The majority of actions a player will execute throughout a game will be to either preseve or increase their power by either avoiding death or securing gold and experience.

Power is determined by: Power is inhibited by:
 * The specific Champion being played.
 * The knowledge and champion control of the player.
 * The experience and level gained.
 * The power curve of a champion based on design / runes / masteries.
 * Itemisation.
 * The current amount of Health and Mana (and other resource types) you possess.
 * The amount of damage output via Skills and Autoattacks available to your Champion.
 * The amount of damage mitigation (Armor and Magic Resistance) you possess.
 * The ability to sustain health and mana, where critical.
 * The presence or lack of nearby Map features: Terrain, brush. (Condemn, Rengar / Nidalee brush mechanics).
 * The specific Summoner Spells in use and their cooldown.
 * Matchups - The enemy Champion/s being played.
 * Any and all enemy Zones which incroach upon yours (see Zones).
 * The knowledge and skill of the enemy player/s.
 * The presence of enemy minions or aggro'd neutrals (block skill shots, damage threat).
 * The current objective/s. E.g. Some Support Champions can crowd control a whole team, but when directed to take down a tower, their power is dramatically reduced.

Power can represent the largest determinant in a majority of trades or fights. Power also usually contributes a greater factor to Zones than Vision. E.g. A champion with a ton of items can still maintain a very large zone even if they have not warded well around themselves. Also, it is important to understand that t he potential to be outplayed always exists.

Power and Allied Structures:

A team's power can be measured by a consideration of the above for each of it's members in conjunction with an assessment of the team's ability to withstand damage to it's Nexus. The Inhibitors and each tower still standing in a lane represent an extension of the team's ability to withstand Nexus damage as each tower must be taken in order within a lane. Similarly, the presence of towers adds to a teams damage potential both to minion waves and to enemies who enter the towers zone.

Give examples for the above / expand ^^

Laning:

For laning, Power and Sustain are interrelated. If you can burst the enemy champion beyond the point of them being able to sustain, then you do not need much sustain yourself. Similarly, if you are incredibly sustaining (Cho'Gath) then your Power.....

Am I missing a concept here?

If your job is to be utility, then isn't sustain a function of your power. I'm just miswording it. Sustain is more important for power in lane. NEED TO REVISE. Outside of lane, sustain is largely handled by choosing engagements / greater regen and lifesteal.

Power assessments should be performed throughout the laning phase with major considerations including the following:
 * How much damage can we trade? "Expand on this?"
 * Who will sustain better? "similar, discuss pots / regen?"
 * What items have they completed?
 * What items have I completed?
 * What level are they / will they be soon?
 * What level am I / will I be soon?

Discussion:

A champion who has significant items and levels can be completely ineffective if the player does not wield the skill to combo skills, position well or land skillshots. In this instance, should power measure the potential for damage / utility of that champion based purely on items / levels? Or should it also include a measure of the player's observed / understood skill level?

This description of power allows for the below case: This is covered by the player's knowledge and champion control. Any good player will abuse expected power spikes and be mindful of the diminishing power they will have upon an enemy reaching a power spike.
 * Current or imminent power spikes granted by experience and level. (E.g. An Annie on level 5 almost 6).

Does this one go in Zoning or Power?
 * The presence or lack of nearby Map features: Terrain, brush. (Condemn, Rengar / Nidalee brush mechanics).

Zones
 * Current or imminent power spikes granted by experience gain. (E.g. An Annie on level 5 almost 6).
 * The presence of nearby allied Champions, minions and towers.
 * Power spikes and skillful play relative to anticipated power spikes.
 * Your power is always relative to the way it interacts with an enemies power or an objective's dynamic characteristics. E.g. Supports can CC a whole team, but when directed to take down a tower, their power is dramatically reduced.
 * The number of enemies capable of applying pressure to you. (Globals, direct enemy champions).