I can imagine a lot of artists have similar approaches to how they do art. They may learn similar techniques to how to shade/light a scene, or even chose similar subject matter - but, the proof of the artist is that very few of us who create our own work, and develop our own style have to worry about others' renditions being so similar that they seem to borrow from us, our style.
I'm still young in the craft and have a lot to learn, but my way of seeing it is that there's lots of different ways to paint flowers, or puppies, or vases - or landscapes, or portraits. just because someone has a similarity of interest doesn't mean that the results will be identical.
One of my good friends took an charcoal class at Univ. - and she showed me one of her drawings once... a wonderful rendition of a naked man... who seemed very well endowed to the point of being 3 legged. I asked her, on seeing it - 'was it really like that???' and her response ... 'no, but it was the only thing that caught my eye' so she drew it out of proportion. In comparing others folders - I'm sure that wasn't always the 'misproportioned' study...
