Rather than a blow-by-blow account of the stories, just a brief general commentary about the Past Imperfect anthology of time travel stories - a DAW anthology from Greenberg and Segriff.
Ironically, for a time travel anthology, most of these stories had a significant problem with pacing. An intriguing set-up and slow build fizzled out or was short-changed; or there was too much moderately dull information before the pay-off.
Two stories stood out as genuinely enjoyable. The first was from Jody Lynn Nye - Theory of Relativity. Close second was The Gift of a Dream from Dean Wesley Smith.
One of the stories was about a character looping back on himself, and reminded me of a story I wrote - Transient - where the non-POV main character lived each day out of sequence. Really should go back to that and see if I can make it flow through ...