The yCRV vault is simply too big. If it switched over to YFII / dfi, the size of that staking pool would triple in an instant, destroying the returns. Yearn is a big fish now, and that pond is just too small for us.
Yes, but this is just an optimization problem in the end, right? We could farm YFII with (e.g.) 15% of the yvault while the rest keeps farming CRV. This might still produce a few percent increase in the total aggregated yield.
As the yvault pool grows, splitting it into various farming grounds might become a necessity anyway.
Splitting part of the vault into YFII is a feasible strategy, but it is questionable if it’s worth spending the effort to implement it, since it will only last a few weeks anyway, due to YFII’s halving rule.
Looking at the pool statistics, I think this would not be an efficient use of resources. The market is quickly moving to correct the discrepancy, as the YFII pool has more than doubled in the last 24 hours, and the next halving will occur in about 4 hours. On Curve, the vault has an advantage that not everyone has (a bunch of CRV from before to boost the returns). In the YFII pool it has no relative advantage.
I don’t think there is a dependable relationship between them, and anyway speculating on price movement is kind of antithetical to what the vaults do (so far), so I would leave that out of this discussion.