Stereo Integrity TM65 MkII drivers...

DrNumbers

Your statement that "In fact, entering the delay, it lessens the distances drastically" caused me to assume otherwise because I don't think calling a 17" difference vs a 16.59" difference for your left tweeter a drastic change. That equates to a few hundredths of a millisecond difference in delay. In which case, that means you must be a true audiophile, because you can hear things that aren't really there.

To more directly answer your question though, both distance and time delay are there to achieve the same objective. Using the milliseconds (i.e. time delay) allows you to do more of a fine-tune. It can come in handy if, for example, you want to shift your sound stage a tiny bit. Reminds me of the judge that said my sound stage was slightly left of center, even though it was dead center... sigh...