paid the outstanding left behind by the errant tenant from my own pocket - not worth arguing with TNB when i'm losing the opportunity to rent my property out.

moral of the story is, take care of your own property whether the account for the supplies of utilities are registered under your name or not because at the end of the day, tenants gets off scot free (especially more so with the Temporary Measures For Reducing The Impact of Coronavirus Disease 2019 (COVID-19) 2020 Act.

Not wrong though, TNB "should" chase the person owing the charges BUT that doesn't mean that TNB will allow new account to be registered for the Property.
The liability to pay rests on the person registered to the account BUT that does not automatically mean that TNB will allow supply until the outstanding has been settled.

2 different matters altogether.
Not rubbish - having the tenant holding the registered account absolves the landlord/owner's the liability to pay the outstanding raked up by the tenant. This means TNB will not issue summons to the landlord/owner for the supplies used by the tenant.

If the account is registered under the landlord/owner however, there is nothing to stop TNB from going after the landlord/owner.

The benefit is that landlord/owners can sleep well at night knowing they won't be forced to pay what their tenant is using.