Gross (Income) is raw money before taxes.

Net (Profit) == Income - Expenses.

I ignore income, as it's fairly meaningless.

Profit, what you have in your hand after you pay your expenses, is real money.

Using the term Gross Profit likely means Pre-Tax Profit.

In other words, after paying your expenses you have Gross Profit. After paying Taxes, you have Net Profit.

I treat Taxes as a hard expense, as you must pay or end up in Club Fed or more likely having your assets attached, like liens on your property.

This writer you mention could likely clarify his terms a bit more.