1 task simultanously by 1 or 2 resources

[jacekkolasa]

Is it possible to schedule 2 resources to 1 task, when they are available, but when only 1 resource is available, it can also work on the same task? Like now I only see 2 options:

schedule.tasks().resources( [ [ 'res1', 'res2' ] ] )
in this setup 'res2' will work on this task only when 'res1' will not be available (I want them to work together)

schedule.tasks().resources( [ 'res1', 'res2' ] )
in this setup they will start work only when both will be available. I want them to start work even if the second resource is unavailable.