I agree 100% TreeDimensional, Dr Ed Gilmans willingness to share his understanding about how when and where to prune is a lesson to all Arb people, its about getting the best outcomes for the tree and people in the
long term. An Illustrated Guide to Pruning should be comulsary reading for all budding CA's.
When it comes to the growth patterns of tree roots unfortunately in many of our super compacted soils the action of trenching tends to produce a preferred growing medium compared to the surrounding profiles, and the pipes make excellent anchorage for trees....but I also have seen, read and heard trees repeatedly being singled out when the evidence for their role in the damage to built infrastructure is sketchy at best.