Yep, I agree. Back in the PNW, any well cultivated soil that we mulched typically got the mulch worked into it due to the soggy conditions and constant foot traffic. Up next to the plants it wasn't so bad, but we had one field of strawberries go yellow one season from too much mulch getting worked into the soil too many consecutive years. Rain and people moving through the field pushed the mulch down from the surface and not only spirged the nitrogen, but also created an impermeable layer that the bushes choked on. We ended up having to deep till the field and fallow it for a year.