There is an area of the yard that had pavers down (was used as a car-pad, I think), which we largely removed. We left a border down, but removed the center, leaving a 5' x 15' bed for me to play with :)

Unfortunately, when we removed the pavers we discovered that there was about 4" of sand underneath as a foundation. Under that is our typical clay soil, full of worms and such since it has been untouched for several decades.

So here's my question - I have read that adding sand to clay soil in small amounts can be bad, but I was wondering if given the large amount of sand we are talking here, if I can just till it into the clay to help with drainage?

Otherwise, I will have to shovel off the top four inches of sand and replace it (a possibility, but my back would be happier not to). I am also planning on adding in compost before I plant.

Just getting into gardening, so if this is a stupid question I apologize!

But remember that there are many other variables that you need to worry about, such as adjusting soil acidity and providing fertilizer and water at the right times. Hopefully, there is plenty of sun in that area, or you aren't going to have much luck with veggies.

If you want to understand how sand interacts with clay and silt to make soil, Google "soil triangle". Loam and sandy loam soils are the best garden soils for general-purpose gardening. If you have clay loam, you can make loam or sandy loam by adding sand. If you have pure clay, you probably need to replace it with purchased soil. My rule of thumb: any soil which produces a good crop of weeds or grass can be amended to make good garden soil.

One of the best things about using sand is that the improvement in your soil is permanent, because sand does not decompose like compost. So you won't have to spend the rest of your life lugging compost and digging it in. On the other hand, it's always a good idea to add a little compost every year. Mulching with compost is the easiest way to do this, and helps to keep the soil cool and moist.