It has to do with your flour to fat ratio...I personally don't like a thin (lots of fat) roux. I prefer one that is heavy on flour if anything. It sounds like your roux was just about right...not to thin. So when you put the veggies in ...they clumped up....Given a little time the veggies would have released moisture and the roux would have thinned out a little....Increasing the oil (or less flour) will make a thinner roux...less clumping....also more fat in the Gumbo. ... After roux cools, often times some fat will rise to the surface and you can pour it off...HTH....Gotta run!!!!
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