Curve is looking into a pool of Yearn vaults and one of the stated goals is to eliminate withdrawal fees:
This will also help users enter and exit pools without paying the 0.5% Yearn withdrawal fee.
The fees were already avoidable by trading the vault token, in Uniswap for example. This will make it easier to avoid the vault withdrawal fees and is somerhing we should consider.
The Curve proposal is here: CIP#16 - Add a new pool and gauge of yvault tokens (yVault yvDAI/yvUSDC/yvUSDT/yvTUSD/USDC) - Proposals - Curve.fi Governance
I posted separately about whether this suggests a vault of vaults to farm CRV, which will potentially be available on a Curve vault pool: Vault of Vaults?