PD only counts as a weapon for engine destroyers.
So, you don't fleet your SM ships? I can see why. Problem is, I don't think non-fleeted ships all at the same time.
What I mean:
Say you have an escort fleet and your SM ship. You need to move them into position to close a warp point. I give orders to attack your SM ship. I know which ship it is since it's the only example of that class in that sector. Now, the ships move. At some point, your SM ship and your fleet will not be on the same sector. If my fleet hits then, your SM ship is totally and utterly screwed.
Then again, at least you didn't run yours into a minefield
As for propulsion experts: So you paid 1000 racial points to move a 200kt larger ship the same speed, effectively
Phoenix-D