No no no ... the only reason I mentioned the Transform tool is because I once had to do sub-titles for a 90 minute film, scores and scores of text boxes ... and the previous editor had done your 'drag-text' technique to position each block ... and because there is no frame of reference (other than the yellow centering lines) her sub-titles were helter-skelter all over the frame, slightly different position each text box. I had to reset every single clip, hundreds, to zero. Then re-set the first clip using Transform. Then I could copy and paste the position from that SINGLE clip to all the other hundreds of clips ... in one click.
But! I totally get what you just showed me about dragging the text itself over to centre it. And I'm TOTALLY grateful for the advice. Thank you Tom...