That's the Honda way. In Honda's if you want to do a change of the ATF, their suggestion is to do drain, fill, drive for a few minutes, and repeat 2 more times. This will basically replace at least 80% of the ATF..

Honda does not recommend doing a flush on their trannys.

 

*shrug* I don't know, all I know is I'm sure it's time for a drain/fill at the very least, because my tranny's been acting atrocious. Studder-type slip when engaging 2nd at around 3500-4000 rpm (roughly half-throttle) and 5th seems to "fall" into gear instead of glide every once in a blue moon at toe-throttle.