The 2005 schedule makes the AMA Guides rating the starting point — and Lab. Code §§4660 and 4660.1 make it presumptively correct, not untouchable. Two doctrines define how far a rating can move and by what road: Almaraz/Guzman governs which number goes in, and Kite governs how multiple numbers combine. Everything else in the pipeline — the ×1.4, the occupational variant, age — runs the same either way.
Almaraz/Guzman — the four-corners rebuttal
In the WCAB’s en banc Almaraz/Guzman decisions, affirmed in Milpitas Unified School District v. WCAB (Guzman) (2010) 187 Cal.App.4th 808, the rule settled here: when the strict, chapter-directed rating does not accurately reflect the impairment, the physician may draw on any part of the AMA Guides — another chapter, another table, the clinical-judgment framework of Chapters 1 and 2 — to express it. The hard limit runs the other way: not outside the four corners of the Guides. An opinion built on non-Guides methods is not substantial evidence, and an A/G alternative without a reasoned explanation of why the strict rating fails is just a bigger number with no legs.
Kite — adding instead of combining
The Combined Values Chart is the schedule’s default: combine largest-first, each addition shrinking. Athens Administrators v. WCAB (Kite) (2013) 78 Cal.Comp.Cases 213 (writ denied) blessed the exception, and the Appeals Board’s en banc Vigil v. County of Kern (2024) sets the test: where the medical evidence shows how each impairment affects activities of daily living, and that those effects don’t overlap or overlap in a way that compounds them (classically bilateral injuries, where each side’s loss magnifies the other), they may be added. On the engine’s standing example: 18 and 11 combine to 27 on the CVC — added under Kite they make 29, and the gap widens as ratings climb. The arithmetic is trivial — the medicine is the fight, and a Kite opinion that just says “synergy” without explaining it invites rejection.
What this looks like in the file
A careful med-legal report states the strict rating, then the A/G alternative with its reasoning, and flags any Kite addition — which means every disputed case carries two or three candidate ratings. The math side of the dispute is fully computable: rate each version, and the spread between them is the exact dollar value the doctrines are fighting over. The decoder verifies either side’s string against the tables; what it cannot do — by design — is bless the medical reasoning underneath.
One caution cuts both ways: neither doctrine is a magic phrase. A/G fails without a reasoned within-the-Guides analysis; Kite fails without substantiated compounding. The schedule’s rating survives most challenges precisely because rebuttal requires work. Case law summarized for orientation; not legal advice.
Rate your shoulder right here
Same engine as the tables above — pick your occupation and age, slide the WPI from the report, and carry it into the full calculator when you’re ready.