[phhlho]

The hardest battles I've had are dealing with legacy code. The majority of teams want to improve the overall code base and correct past mistakes, but you can never fix everything right now. Deciding when to let the nasty thing lie and when to pay the cost of fixing something is a tough decision to make. Fixing costs are large and immediate but the cost of leaving a problem area is spread unknown across the future. Couple that with fixes that don't actually provide system value except for standardization and you can have all sorts of fun arguments.

[dclowd9901]

This is something you have to decide organizationally. For our part as a frontend team, we've decided when we implement a new feature, it won't be in our old framework. Ever. We've built a way to integrate React into our old world areas of our code. Furthermore, the portion of the old world code that this new React code interacts with will also be converted into React. This way, our code has a sort of 100%+1% movement toward the new framework.

The point is, you need to figure this out as a group and then just implement it as a rule. It can't happen during the code review.