I think you might be missing the point. But here's the entry:
As mentioned in the OP's post, Inspire Courage lasts for as long as the bard is singing and for 5 round afterwards.Inspire Courage (Su): A bard with 3 or more ranks in a Perform skill
can use song or poetics to inspire courage in his allies (including
himself ), bolstering them against fear and improving their combat
abilities. To be affected, an ally must be able to hear the bard sing.
The effect lasts for as long as the ally hears the bard sing and for 5
rounds thereafter.
Melodic Casting allows the bardic music to work differently for spells and spell-like abilities. You're still screwed for melee.
So, when you use Inspire Courage and Melodic Casting you do a concentration check by using the concentration skill or a perform skill check and then you maintain the benefit of Inspire Courage while casting a spell or using a spell-like ability at the same time.Benefit: Whenever a Concentration check would be
required to cast a spell or use a spell-like ability (such as
when you cast defensively or are distracted or injured while
casting), you can make a Perform check instead.
In addition, you can cast spells and activate magic items
by command word or spell completion while using a bardic
music ability. Bardic music abilities that require concentration
still take a standard action to perform.