Digital BW, The Print

Since we lost the ability to profile ABW mode, I've decided to start working with adjustment curves to compensate for any problems with the linearity of the print driver.  I've never really used .acvs before, so while I understand the idea behind them, there are a few things I wanted to clarify. 
I downloaded a handy Excel utility (it came from one of these groups, so I'm sure many of you have it) that has you paste the density measurements from a 21 step file, and it tells you were to place the points on a curve.  I assume I'd print it the way I normally would for any file (printer manages, relative, dark), but I'm not sure what to do about assigning a profile to the target before printing.  Obviously for profiling, I'd want to leave it untagged, but since this is a little different, I'm thinking I should assign something.  Gray LAB is the most linear, so maybe it makes sense to use that, or knowing the print driver sends everything as generic gray gamma 2.2, perhaps I should use that.  Or do I just use my normal working space, gray gamma 2.2.  OR am I overthinking it (shocker), and I should just leave it untagged?

Then this might be a dumb question, but the Excel file generates more points than Photoshop will allow me to place on a curve.  Is there a way to convince PS to let me add more points, or should I just skip some in the more linear parts of the curve?

So in theory, I should be able to confirm that I've done everything correctly by applying my .acv to the 21 step file, and having it read perfectly linear, right? 
Given that they've removed the option to use profiles with ABW, is this the best alternative, or am I going about it the wrong way?

I'm running an 11880 on snow leopard with CS5.

Sorry for the long post...
Thanks for any input!