It's a pity to lose the bonus to woodcutting from the axe upgrades. There is no market to trade the extra wood so it was not really unbalanced.
Viewing post in 0.6.1.0 - Improvements and balance changes comments
Thanks for your comment! We ran some numbers that told us that it made the upgrades too strong compared to other equipment upgrades. We're definitely going to add a market so trading extra wood will be possible. One of the biggest (might actually be the biggest and most obvious) issues of the games right now is that trees run out and all buildings military units (except Heavy Axeman) costs wood to train, so it's something we really have to look into soon.