is it better to use a non-clustered index in a large delete? i thought it was the opposite since you would be deleting data that is logically together in the table

years ago i saw an issue where large amounts of data was inserted, deleted and modified on a non-clustered index and it cause a lot of blocking when the app changed to use multiple threads. we changed the clustered index column and the problems went away since the data that was changed was on the same pages and extents