(New member), curious on this article, because I always considered that in achieving a good bonsai, or miniature root pruning is important, keeping that balanced broom-style, needed for small trays, and depending how "minature" I want it, cutting the central tap root quite often, but really never ran into something that my small rake, and hook couldn't handle, the article, (I did not read the first thread), remainds me of what I run into with my landscaping trees.

When working with large nursery trees you are in essence working with landscaping trees. The major difference is that most of the trees you find that are good candidates for bonsai are not necessarily good for landscaping. In fact most of them are pretty bad for landscaping and have been hanging around the nursery for several seasons. When this happens the root systems become really tangled and convoluted.

The bad aspects of them become worse and the good aspects degrade. So in the end, as far as the bonsai grower is concerned, you have to deal with all the "to be expected" problems compounded by several years of neglect.