Technical Depth Calibration
Matching the level of detail and the mode of engagement to an engineering audience, which needs reasoning and the opportunity to disagree.
The failure with engineers is the opposite of the one with executives: too little detail, and a conclusion presented without its reasoning, which reads as an instruction rather than a design.
Engineers evaluate a design by reconstructing the reasoning. If it is not supplied, they will assume it does not exist, and the objections will be about the parts they had to guess at.
What an engineering audience needs: the constraints and trade-offs, including the ones that were uncomfortable; the alternatives considered and why they were rejected, which pre-empts the most common review comments; the specific mechanisms rather than a diagram of boxes; and the parts that are uncertain, stated as uncertain.
The most important element is not informational: a genuine opportunity to disagree, early enough that disagreement can change the design. A decision presented as settled will be complied with and not owned, and the difference shows up in implementation quality months later.
Two habits that build credibility with this audience specifically: saying "I don't know" when that is true, and changing position publicly when someone produces a better argument. Both are read as signals about whether the reasoning is honest, which determines how much of the rest is believed.