Ask HN: Upvotes have seemingly new, limited effect or delay

I realized today that my upvotes on comments have either delayed or no effect, while my upvotes on submissions seem immediate, but with the odd inability to unvote without a long delay or no effect. To test this, I did the following:

1. COMMENTS: Upvoted several recent comments of different users through different threads. Refreshed their user profile in separate tab (multiple times) and observed no increase/decrease in karma. Same results when going back and forth refreshing same tab. Removing cache nor using a separate browser (not logged in) had any effect.

2. SUBMISSIONS: Using the same method as above, I upvoted several submissions in new (but older) status. Strangely, the submission would rise by one point, but after unvoting, would remain unaffected, but possibly retract with a significant delay.

I can certainly imagine a purpose or reason for delays, but I'd never noticed previously. My effect (or ineffect) on comments does seem new.

Is this behavior induced moderation voodoo, or standard?