I always delete history before binding. I also freeze the transformations, to get rid of any affects to transfroms and scales, etc.

There isn't really any set rule that I know of for when to delete your history. Just know what when you do, it's effectively "baked" into its current state, so only do so when you are happy with a model at that state.

For example, if you smooth an object to see how it looks smoothed, but do not want to keep the smooth, then you would not want to delete history, as then the smooth would be permanent (barring undos, of course).