ORIGINAL: WA Shooter
It would indicate a weak spine, but at 60# with a 28.5" GT 5575, I would think the spine is OK with a 100 Gr. tip.
Did you try this arrow with a 125 grain point? According to OnTarget2 the arrow is a little stiff. Of course as Rick pointed our, OT2 tends to recommend weaker spined arrows. Also, I am making a lot of assumptions on your bow that could significantly change the spine recommendations.
Checking with heavier points would be a cheap way to test.