Yeah, not going to dispute that the series overall had some bewildering and sometimes downright bad episodes mixed in between the treasure trove of gems (Sub Rosa being an odd duck for being both THAT bad and that late in the series).

I guess that's what happens when you have multiple writers running episodes in parallel to each other. Nowadays (with all the explicit continuity series go for) that's less likely to happen as writers are at least expected to have plot and tone carry over between episodes, but for older episodic "villain of the week" type shows like TNG it id more likely to happen.