Growing Things: Many ways to manipulate soil

Q I have been amending a flower bed that I want to put some plants in next year. I thought I had beautiful soil until the rains came and I found the plot was clay. Two years ago I kept adding grass clippings throughout the summer. Then in the fall I tilled lots of leaves. Then this year I added more leaves, grass clippings, compost, and chunks of lawn. I double-dug the soil this past fall adding large quantities of leaves, compost and more leaves. Is adding too many leaves a problem? I have hear