No, there is differently something else going on. You can definitely make the tree cutting take longer with encumbrance, exhaustion, low skill or bad tools but you can't reliably cut down trees much faster than that.
I've created a new character, 98% starting timbercraft, extremely high starting attributes and a masterwork Woodsman's Axe. Fully rested, no items except the axe and cutting down the tree still took around 40-50 minutes on average. There were a few cases of it being closer to 30 min, but there's no way you can cut down the tree in ten minutes, regardless of circumstances. Best skill, circumstances, equipment and a very lucky roll can maybe get you a tree down in 30 minutes.
That's still a far cry from an NPC with good skill but substandard equipment (just a handaxe), chopping down tree after tree in around ten minutes each.