I run the leaves for my spring bulb beds through the lawn mower, which is more work, but the chopped leaves stay fluffy and don't mat. I've had problems in the past with bulb shoots growing up through whole, wet leaves, especially with tulips. Picture the leaf with the shoot having pierced it and growing right up through it. When the leaf dries, it squeezes the shoot and prevents it from unfurling. This usually results in misshapen leaves. For the rest of my beds, I just leave the leaves whole.