The issue was that Starting balance field was misused. Because it was so easy to use, people were using the field in established businesses which was changing their financial statements retrospectively without realizing. This was creating issues elsewhere down the line.
In some cases, people were periodically updating their starting balances to simply adjust the figures they want to see on their balance sheet.
In the end, Manager needs to be making the wrong thing difficult to do. Not easy to do. Doing the right thing is important so you are not creating extra work for you and your accountant at some later point when things need to be corrected.
As for the guide, new guides are still light on information but getting there. Here is the guide on fixed assets: