What exactly is meant by 'scaling up'?

'At the same time, the practical approaches that we do have, have remained perhaps too limited to certain specific techniques or topics. We must develop a broader understanding of how to link and expand specific techniques to achieve cross-cutting practical solutions (eg...neighbourhood rezoning to reduce the need for automobiles).' ->is this really a matter of a lack of understanding, or is it rather a question of power and politics? Rezoning can hardly be done by grassroots communities...isn't democratic/citizen partizipation a factor here?

Evaluation of failure/success: Yes, this is an important consideration. Not all projects work out even if a lot of effort is put in (as we have experienced in a local transportation initiative); reasons are not so clear; evaluation would help to learn for the future.

Link to paper by Narberhaus: establishing educational framework, bridging theory and practice etc seems to cover the niche- and the culture-level; is regime level also covered?

It is a political scaling up. I meant to refer to the process on local, atomized initiatives, although with similar meanings/values, build up collective action and enlarge their transformation potential from the local towards the regional, national, global.

I believe and have observed that the most effective experiences are those articulating a series of strategies. This is actually coherent with the often mentioned idea in degrowth literature of relying on multiple parallel strategies. For the particular example you make @arndt, the "sufficiency politics", see for example the stirring paper of Schneidewind (“Politics of sufficiency” as politics for the good life), also expanded in a German book.

Evaluation is definitely central. However, it cannot be an expert-based evaluation, such as inquiries or evaluation forms done by organisers, consultants or even researchers. To be able to respond to the complexity of the problem to be reflected upon, as well as to embed the democratic dimension of degrowth, this requires a process of what Funtowicz (post-normal science) called an extended peer review. The whole process of evaluation is conducted by the community of peers, which consists of all actors affected/involved by the issue/project.

The objective of the evaluation process is also not necessarily to make clear why a project failed, but rather to have a continuous and cummulative learning process within the existing and emerging communities of practice. The articulations (feedback loops) between this learning process and the theoretical research on degrowth is then another important aspect to deal with.