It's unfair to hold back the best scores. If someone just tries to beat the current best score only to find that the real score is much higher, he will be disappointed. We had that situation a few years ago, I was accused of playing dirty then, so after that discussion I decided to always post my best scores immediately.
As for pacing myself, I am. I have played this for about three hours, tops. You can get that score easily if you concentrate on getting the bonus word spelled right away and then concentrating on collecting as many letters as you can (200 points each after having spelled 'bonus'). Don't bother kicking the enemies, you get more points by collecting the letters. It's mandatory to have the bonus and land on the 3,000 points platform, this gives you a 15k bonus.
If I miss spelling the bonus, I restart immediately. Since the layout of the levels and the spawn points of the enemies and their moving patterns are always the same, it's pretty easy to find a strategy for each level. After that, it's rinse and repeat until you get a good run.