Poul Anderson,
1980alpha IN Anderson,
The Shield Of Time (New York, 1991), pp. 284-292.
(Life really has become busier here. After a morning at the gym, I must shortly travel by train around Morecambe Bay to meet former work colleagues for a curry, thus missing the Light Up Lancaster Festival.)
Keith Denison's (second) capture serves his author's story purposes but how plausible is it? When it is immediately apparent that Denison has arrived in the wrong timeline:
"Shock froze his hands on the control bars." (p. 284)
Surely trained reflex should have made him depart immediately? Instead, he is described as:
"Untrained for combat missions..." (ibid.)
- and, because he hesitates:
"A man in blue..." (ibid.)
- a policeman? - is able to pull him from his timecycle while the rest of the alternative historical Parisian street crowd is still reacting in panic with prayers and invocations.
The one thing that Denison does do right, and by reflex, is:
"...to hit the emergency go-button." (ibid.)
This is because outsiders must never gain possession of a timecycle.
"His disappeared." (ibid.)
And that leaves Denison exactly where Anderson wants him, trapped in the alpha timeline and able to learn something of its history before he is rescued by Wanda Tamberly.