So I have read comments and understand that the hole creates a wound that eventually becomes a 2 foot tall by two inch or so wide, stretch of dark wood that will never flow again. I wonder then, if the 'scab' for lack of better term, as the tree initially heals and closes, takes time to generate up and down from the hole. If one were to tap another hole just two inches above the first, dried up hole, would it run for a few weeks. If it did, then the stain would not be significantly bigger, and may not affect the tree at all. Or similarly, a new hole couple inches below. If however the scab, stain area takes on the entire size immediately and progressively shuts off and darkens, then this would not work at all. In this case, again, no more real significant damage to the tree.
Right now, mixed bag. One good producing tree has shut off, others are doing as good now as ever, all put in Feb 5.
2014 Year 1, 1 large front yard shade tree with 3 taps - 3 quarts of the best syrup I ever had.
2015 - Convince In-laws and Neighbors, bought F-150 and bricks. 20 taps, 4 gallons in pretty bottles.
2016 -- More friends and neighbors, should add another 20 +, built temporary shelter as sugar shack. F150 traded for Ram 2500. Big Blue new barrels for 116 gal storage. 8 gallons Syrup.
2017 - Mortared Brick Arch with serving pans, no make that an 18 x 48 CDL divided flat pan, 48 taps.