The expert’s strategy is not 100% wrong, because it does not take into account actual pay-tables on individual slot machines.
Slot machines all publish their pay-tables, and some DO NOT PAY certain jackpots UNLESS you play maximum bet. For those machines, maximum return can only be achieved by betting the maximum. betting the minimum can actually cause you to lose a significant jackpot because of the posted pay-table.
It’s not right or wrong, it’s what works for you. Slot machines today take bills, and max bet is sometimes $6 or more per “pull”. When you calculate your “dollars bet per hour” bet, keep an eye on how much you can lose. Think about becoming a Session Gambler. And remember to have fun in the casinos!