Back in the 1990's I did some work with Pat Slaney and Bruce Ward on the Squamish, which eventually became the working model for WRP in the NDP days before Gordon Campbell axed it. As was noted, some good preliminary work stream complexing, off channel habitat, ground water upwelling spawning platforms, even some fertilization. All great stuff, which many dedicated volunteers, DFO and Prov of BC staff contributed blood, sweat and tears to implementing.
One lesson learned, by me at least, was habitat work without addressing other issues such as recruitment that ensure bio-diversity and sorting out the ocean survival bottle neck....well, are just icing on the cake. Nice, but largely ineffective at achieving recovery. Nature is random, complex and as humans we all too often look for singular and simplistic "silver bullets."
Our resources and time are not limitless either, so while we would all love to do everything I also have been learning its sometimes better to try to address the largest barriers to recovery as a first priority then move down the list in rank order unless there's some easy low hanging fruit. Habitat work is expensive and in most situations isn't the biggest barrier to recovery. Before someone roasts me with an example like the Big Bar slide...that's the exception to the norm.