On-chain strategy logic is expensive to run and slow to react. Sommelier's answer is to compute decisions on a separate chain, where computation is cheap, and relay the resulting instructions to Ethereum vaults for execution.
What the architecture enables
Strategies that rebalance on shorter timeframes, respond to market conditions and implement logic too complex to run economically on Ethereum. Named strategy providers publish mandates, and the vaults execute what the chain's validators approve.
The trust assumption
Your vault's behaviour depends on a validator set reaching consensus on what it should do. That is a governance layer between you and your funds which pure on-chain vaults do not have. Sommelier documents this and constrains what strategies can do through on-chain guardrails, but the fundamental point stands: someone can change what your capital does without your action.
Performance and fees
Roughly 1–2% management plus 10% performance. Strategy results have been mixed, which is unsurprising — active management is difficult and most active managers underperform in any market.
Who should use it
Depositors who want actively managed strategies and accept validator governance over vault behaviour. Those who want strategy logic they can read and that cannot change should use a vault with immutable on-chain strategies.