Original sentence: Armstrong's writing and broadcasting style, no doubt spurred by a rapidly developing geopolitical world, exhibited what some would call a tendency toward sensationalism that would be the source of controversy for supporters and critics alike from that point until his death
Edited sentence: It was during this period that Armstrong, no doubt spurred by a rapidly developing geopolitical world, began to reveal a tendency toward sensationalism that would be the source of controversy for supporters and critics alike from that point until his death