Considering that at present the intended strategy is only a part of the realised strategy, it is necessary to take into account emergent strategy as quick as possible. Developing a strategy for 3 years and and reviewing it only once (mid-term review) is not sufficient. Strategy and related portfolio should be changed more often.
The explicit linking between business priorities and IT projects (see illustration below from http://improving-bpm-systems.blogspot.com/2013/02/linking-business-strategy-and-it.html)
- guarantees implementation of the strategy,
- simplifies the strategy review and
- changes such a review into routine activity.