Facebook friend David Spinelli was kind enough to alert me to several online links/ articles of interest related to the LBJ-killed-JFK scenario, including the use of a double for LBJ. As far-fetched as the "double" notion may seem at first glance, take a look at these articles:
LBJ's Double – Cousin Jay Bert Peck – And his Untimely Death by author Phil Nelson ("LBJ: From Mastermind to "The Colossus"):
excerpt-"According to Billie Sol Estes, Johnson had Peck “stand in” for him the evening of November 21, 1963, so he could go to the Murchison party and give the final go-ahead nod for the assassination, secure in the knowledge that Peck would only make a brief appearance to throw off reporters as to his whereabouts. The reports that Johnson was seen that evening at the hotel in Ft. Worth in the main dining room and lobby could be explained by this device, considering that there were no indications that he spoke to any group or even to anyone in particular that evening. (One longtime researcher who wishes to remain anonymous and who knew Johnson’s lover Madeleine Brown said that Ms. Brown believed that Johnson had Captain James Swindal, who flew Air Force One, fly him in a small airplane to the smaller Addison Airport, which was only a mile or two from Murchison’s mansion on Preston Road in north Dallas. Other researchers are convinced that Johnson had his Secret Service agent, the sycophantic Rufus Youngblood, drive him to the Murchison home at Clint’s insistence, which would explain Johnson’s surly attitude upon his arrival there, as described by Madeleine Brown)."
NOW, FROM MY BOOK "SURVIVOR'S GUILT":
Page 264, based on Secret Service Agent Rufus Youngblood's report in Volume 18, pages 681-682: Interestingly, while others slept or were out drinking in Fort Worth, Youngblood left in the early morning hours of 11/22/63, supposedly to visit a childhood acquaintance, a detail not mentioned in his LBJ Library oral history, his book, or anywhere else since he noted it in his report.