The quotes above are copied and pasted emails sent back and forth.

I understand about the coating and seam sealing. However, I think that other large manufacturers are using the slightly heavier fabrics, sealing them, and producing tents that weigh as much or less. For instance, I bought a Copper Spur tent from Big Agnes. It has a higher space to weight ratio and is completely seam sealed. Several of the tent companies quoted above are small companies and I completely understand how they may lack the manufacturing capabilities of larger companies. If I bought one from Henry Shires or from Warmlite, or someone, I wouldn't expect that they seam seal the tents. However, I think that both of those companies at least make the seams on the tents easier to seal and use fabrics that can be sealed well, unlike Black Diamond.

Really, how much more would it make a Black Diamond tent weigh if they made the floor with the PU Coating and seam sealed it? Honestly, I don't know and I'm wondering.

I am willing to bet that it has little or nothing to do with the weight of the tent. How concerned about weight can they be when they leave almost an inch of excess fabric hanging out of the seams on all of the pole pockets? I think that, more than anything, they don't want to incur the additional cost. I understand that but I hope that, with that decision, they also incur less brand loyalty.