| >>Given that you've set a hard deadline for the respec, how does the fact that I doubt the mech split will be done by that time work?|
You'll be able to split your mech into Forging, Outfitting, and Engineering when DR3 comes out - In the month+ you get for respeccing, you'll be able to make those splits. If you decide to wait until Enchanting or Alchemy are available AND want to split your remaining mech ranks between the two, you'll end up possibly losing TDPS, and there won't be a respec available to you for that, necessarily. In general it won't be a huge number of TDPs anyway, because one skill isn't as big of a deal. Let's say you had 750 and it split into two at 500 - You'd have gained 1252 TDPs from your two new skills and lost 1408, for a difference of 156. That number get smaller the less evenly you split them, but to be honest 156 TDPs isn't even one stat point for a human with 70 in the stat.
Now, I'm not sure that it'll be 500 ranks in each if you split 750 - Still working on the split values. That should give you an idea of the magnitude, though.