Budget Process Review Group, Final report, 30 June 2017The Scottish Government implemented this recommendation when publishing the 2019-20 budget in 2018, and since then a section responding to committees' scrutiny has appeared in the main budget document.
The Scottish Government's website currently explains that the process with regards to committee scrutiny is:
We respond to their suggestions in the Budget Bill supporting document, then debate any proposed amendments in Parliament prior to stage 1.