Breaking into a formation

I recently was asked my opinion on what I thought about breaking into the line of a biker formation with a car. Meaning when a group of motorcyclists is riding in staggered formation, clearly riding together as a group, has a car merge into the formation. The person who asked me used to ride, so he does have a clue, and does respect bikers. He said he was following about 15 bikers riding staggered formation, on a long winding hilly road. The group of riders was going about 5 M.P.H. under the speed limit for a very long time, and were holding up quite a line of traffic behind them. It was a difficult road to pass, with little opportunities to do so. He said there were four other cars in front of him, and the opportunity came to pass, and as a group of 5 cars, they all went to pass the biker group. He said just as the other four cars made it, a vehicle was coming around the next curve, and he realized he was not going to make it. He said he could not merge back into traffic behind the group, because he was so close to the front already, and would hit the oncoming car head on if he waited that long to fall back. He said he had no choice but to turn on his right turn signal, and pray that the group of bikers would let him merge into their formation. They did, and he did. He said not so much by either of their choice, but it had to be done. He felt they would understand, and give him a break, and as first opportunity would come, he would let them resume without him in their line up. The lead biker (Lets say Road Captain) Freaked the Fuck out. (He could not confirm if this was a HOG organization, or MC, or just casual group of friends riding together. He said he thought the latter, as no one had on any colors. Anyway, the leader would not let him pass. Would not let him do anything. Every time he went to get out of there the biker sped up, and got in front of him and slowed way down to like 30 in a 55 M.P.H, zone, furthering the traffic delay they were creating in the first place. He said this went on for about 15 miles or so, before he finally turned off. I said etiquette wise, probably not wise to break biker formation. Consider it one unit, like a really long truck. Watch as most times at an intersection if a group is riding in formation, they will proceed through an intersection as if they were one vehicle. I did mention that the lead biker sounds like he had his undies in a bunch though. I would have given the guy a break.

What do you think?