Algorithm difference between tab to transient and option + tab to transient?

[taiga_with_a_pen]

This isnt really a problem or anything, rather a quirky little thing that Ive noticed about tab to transient that Im hoping someone could maybe shed some light on.

So I was quantizing guitars this morning using tab to transient, and I accidentally hit the tab key twice, skipping over one of the strums. After realizing I had skipped a hit, I did an Option + Tab to go back to the transient only to notice that the edit cursor was now at a different part of the skipped transients attack then it was before I skipped over it.

Now what I can gather from this is that using option+tab to transients as oppose to hitting the normal tab to transients will place your cursor at a different part of the notes attack. Does this happen to anyone else? Why might Pro Tools be detecting the transients so differently?