Yes. It does!
In fact Business Case writing is a mini-project in it's own right as it involves almost all the facets of project execution and management aspects.
Proposal building, Business Case writing and eventual Project Execution are inter-related to each other. At times Proposals received from different sources (internal/external both) act as input to the business case writing. One of the best proposals makes an entry into the Business Case's recommended option. Further this proposed solution approach/option is then taken for execution.
While the business case is presented in a well structured written document, but it may also sometimes come in the form of a short presentation or even a verbal argument. However, Critical projects' selection is always done through an effective business case writing process.
Business Case is not just a guiding tool for the senior management to decide on a particular project with a recommended solution approach but also it provides for the framework for the selected project's execution. For this very reason, business case writing is very important. Business case writing goes through the proper project management process. Like formal project management, business case takes into consideration effective stakeholder engagement/management, estimation, costing, risk assessment, resources' assessment etc. Effective business case writing relies on Organizational, financial, managerial, technical, human resource, contractual and procurement skills.
A successful business case is expected to meet the organization's strategic, economic, business, financial and feasibility criteria.Like project execution, business case writing also makes use of quality gates as it is also authorized by the appropriate body at each phase of its development. The project is then executed against the success parameters as agreed in and made part of the business case. Business case is referred throughout the project life cycle and not just during the initial project selection phase. During the project execution, senior management always compare the project's current status against the agreed criteria in business case. In case the project is found to be deviating from the agreed terms specified in Business Case, the project may be scrapped or terminated. In short the business case acts as the baseline document for the project execution and hence has to be carefully articulated and written.