Measure Twice?

We've all heard it before. Measure twice, cut once. In working with wood I generally do just that. There's another one about you can always cut more off, but you can't stick it back. Probably with that in mind I'm always careful to leave just a little more wood on the 'safe' side of the cut. I'm currently making a small 'chest of drawers' in American white oak. Lovely wood to work. It's for a set of cutlery. 24 pieces, six drawers...here is the front. I was asked to add another drawer (bottom one) for a possible carving set. I've made a chest of drawers before. In ash. Not such a nice wood but it all worked out well. I've been thinking of this for some time, drawn in out on qcad it has come together quite well. I started cutting yesterday and it came up some two mm larger than the drawing (width wise). When it came to cut out the rebates for the vertical partitions, I only measured from one side and the one mm difference in the line up looks horrid. Surprising how accurate the eye is at catching those inaccuracies. I cut some more wood today and after marking up one as the reference, I cut a further two from this master; leaving a truly vertical (and matching) set of three vertical pieces, all nicely one on top of another and boy does it look better. Tomorrow I'll cut out the housings for the panels and start on the side pieces. Another lesson learned. CAD may be accurate, but it's the woodcuts that show up!