Alternation between two stories and suspense

Capote uses very interesting methods to increase the suspense that the reader feels. One method that he uses from around page 17 to page 32 is that he alternates between two stories. He gives a few pages towards the story of the Clutter family and their friends, then a few towards explaining what Perry and Dick are doing. This seems like a fairly natural thing to do: it keeps the reader interested because there isn't just one plain storyline. However much of this alternation is used for the purpose of raising suspense. One method of this is that in each story individually, more and more seems to be going on. On the Clutters' side Capote talks about Nancy's hectic schedule, the Thanksgiving gala that Mr. Clutter needs to prepare for, and more. And on the subject of Perry and Dick something suspicious seems to be going on. Capote reveals this through his language among other means. On page 23, after explaining how Perry and Dick fixed up their car, Capote goes on to say "...all necessary undertakings, for between today and tomorrow the aged Chevrolet was expected to perform punishing feats." This implies that something important is about to go on, and by using words like "punishing" Capote reveals that this undertaking may have some deadly quality to it. At this point the reader has an aching suspicion that these two stories are going to collide and that something catastrophic will occur. Capote even goes as far on page 30 as to blatantly say that Ms. Clutter is going to die: "Now, on this final day of her life, Mrs. Clutter hung in the closet the calico housedress she had been wearing..." However this still contains much suspense because, as is supposedly inscribed on a bookmark, "ye know not when the time is." (this quote is also on page 30) I suspect that this is made up, but that's another story. Capote's methods for creating suspense are pretty creative, and by occasionally putting in a blatant statement as described above he keeps the reader in a state of unrest.