It
does work the way Terence2112 has described it. If you have 7 concurrent employers in Singapore each paying you $6,000 per month or more in regular wages/salary plus $30,000 or more in variable pay, then yes, you would have $37,740 * 7 = $264,180 streaming into your CPF accounts. Plus possible AMCS dollars streaming into MediSave on top of that.
Needless to say, this situation is rare, but it can occur with highly compensated individuals who hold multiple corporate directorships, for example. Also, such individuals can choose to opt out of the employee contributions above the employee share of one CPF Annual Limit, but the employers must still contribute their portions ($17,340 maximum per year per employer, plus any AMCS dollars).