Hopefully 15% is for ( Total - 750 )
More accurately, this is a form of alternative minimum tax- a higher floor than the normal brackets specifically for those who cross a specific threshold.
That does carry a hefty incentive to play games with your accounting, and is ultimately rather foolish since the people it was really aimed at when introduced in the US shifted their income to capital gains instead.
Now, it is mostly a way to punish people for becoming upper middle class.
Personally, I think the tax rate should be higher than 15% for all corporations so I'm not so worried that a company might miss out on an even better deal of 12.5%, but I see the concern that a small change in revenue might change their tax bill by millions.