I enjoy the idea of the shifting refrain -- it's a nice simple line that works well. I'm not convinced that the setup is strong enough though. The poem flat-out states "it's an easy thing" and then "it's not so simple after all", and I feel the first stanza should be delivered with a little more sarcasm or flippancy. For example, "Yes, it's such an easy thing" gives the impression of a direct reply to someone's rather ignorant assertion.
There is a kind of poetry form you might like to look into called the quatern, which uses a similar kind of pattern to yours only with more structure. If you want to practise you need only yell at one of us to give you a hand.
There is a kind of poetry form you might like to look into called the quatern, which uses a similar kind of pattern to yours only with more structure. If you want to practise you need only yell at one of us to give you a hand.
It could be worse