Nice thread, just wanted to share some extended info on wood chips, although i could go on for a while about worms too.
Ive trialled some decomposition of wood chips and found some supporting info that seems consistent with what Ive seen. I have basically an endless supply of chipped materials and access to large swathes of land for experimentation and this is what Ive found.
Nitrogen tie up is less of an issue than is commonly considered. What really matters is the
type of wood chips.
Chips of heartwood and especially hardwood heartwood, even sawdust for that matter
may tie up Nitrogen, but this effect on a decomposition point of view is still fairly short, 4 seasons and there shouldnt be any further effect. This is bourne out in natural forested areas, Nitrogen feeders will still establish and grow in the vicinity of heartwood decomposing, but the effect is not as great as some claim.
Further to this chips which have leaf and outer branch matter integrated will cease tie ups
much sooner than heartwood chips only. The most favourable chips are finely shredded leaf and outer branch material, N lock is virtually negligible and decomposition starts much sooner, similar to leaf litter cover in forested areas.
Ive used all sorts of chips to create soil, and found what i have concluded above is accurate. Ive tried to keep this as simple as possible in explaining.
Macro testing has been done on many acres and using differing materials, all regulated soil tests in certified agricultural labs have shown broken down chips to have greatly improved soils when added to the top layers (I certainly wouldnt advise digging in on a small or large scale) in nutrient levels, activity and moisture retention, without depleting baseline N levels.
I wouldnt go as far to say its a myth, but its certain to me the effect in unsubstantiated literature available (some garden gurus with zero evidence or substantiated explaination of
how this occurs) is not bourne out in meticulous agricultural testing.
As an aside I have 3 year old pine chips on the south side of my garden a couple inches thick, earthworms are active with in about 10 months of the year, when I screen it in an A4 size mesh screen it not uncommon to get 5 to 10 healthy 3 to 4 inch long earthworms from it, they love it.
My interest in gardening and small to mid scale farming has been a long one, and I was in Waste management with local government for quite a few years where we partnered with local agriculture to find uses for greenwaste, trials were undertaken less than 10 years ago
got 3 compost bins 2x500L and a 260L composting materials will mostly be grass garden lawn clippings,teabags debaged as teabags have plastic in them 
who knew.and junk mail 
