smoking the leaves will be harsh but they will also get you high(unless its a fan leaf). when a grower manicures they bud they usually cut all the small little leaves off and use it to make hash...but if its commercial bud i dont think the grower is going to spend all his time trimming up the bed the best he can because it can be very time consuming. So the little leaves left in the back have THC but they also have chlorophyl and nitrogen which gives it a harsh taste.