That's a logical fallacy, if everybody else does it, it has to be correct. Most NFL coaches are conservative because being "bold" labels you a "riverboat gambler" and risks you losing your job. Not everybody is secure in their position like Belichick or even Harbaugh (either one) and can afford to take the non-standard play even if it's the better one. The reason is simple, let's say a particular situation has a positive outcome only 20% of the time. Do you want to be conventional when the outcome fails 80% of the time or do you want to look like a lunatic?
So to you it makes more sense to do the thing that only has a positive outcome 10% of the time? 5% of the time? Its pretty simply...20% outcome is better than any value less that 20.
This is explained well in the book Scorecasting. I know it's an entirely different game, but there's a successful high school football coach who never punts and doesn't even keep a functional punter because he's looked at the probabilities and has decided punting is the sub-optimal decision. Now nobody in the NFL would ever do that particular play, but that doesn't mean established doctrine is always right.
I haven't read anything in depth on this coach, just a couple of articles to understand the point you are trying to make. He almost never punts. He looked at the stats and figured when it made sense and when there was no benefit. He is basing it on numbers, not hoping something improbable might happen just because he is doing something different.
According to his analysis, a college team that fails to make a fourth-down conversion near its own goal line gives the other offense a 92 percent chance of scoring a touchdown. But punting the ball from such deep territory only reduced that chance to 77 percent.
http://swtimes.com/columns-blogs/steve-brawner/commentary-pulaski-academys-coach-kelley-congress
Now the article didnt say what his teams 4th conversion rate was, but it must have higher than the difference of his teams 4th down success rate at various distances vs punting on 4th down on his goal line.
Sportscasting might imply that some of the stuff coaches do merely risk aversion, but that implies the coaches are doing the safest thing possible. The numbers are still in their favor. A couple of years ago in the playoffs the Patriots went for it on 4th down, in their own territory, and it didnt work out. It gave the Colts a shot field and then the game. USC did a similar thing in the BCS title game against Texas, and again, they failed, gave Texas a shorter field. Now I would think the Patriots could get a yard in that scenario, and the way Lendale White was running all game I would have thought they could get a yard as well. Even if you looked at stats, you could probably justify it, until you look at the game situation. But hindsight is always 100%. Those teams in those situations, you dont expect them to fail. And if the Patriots or USC (in their prime) couldnt do it, lesser teams would have a hard time justifying it.
Doing the "risky" play doesnt always work out, otherwise it wouldnt be risky. While I agree that coaches are somewhat protecting their careers, the way they protect themselves is by winning. No one saves their jobs by playing it safe and losing.
Back to the game itself, with just one timeout, the Chargers absolutely had to force a turnover to get the snowball's chance of tying/winning the contest. Again, this is not the NBA. 2 seconds is just not that important because the clock hardly ever stops immediately on the whistle anyway. ALL ELSE BEING EQUAL, if you miraculously get the ball back with enough time to run at least a few plays, every head coach will trade 2 seconds for a time out.
How are you saving this timeout? You need the ball back first, and the odds are the only way you do it is by forcing a punt. The odds of forcing a turnover are far less likely, because the other team knows this as well. 2nd down at 2:02 or first down at 2:00 still means you need to use a timeout to get the ball.
You need to tune out the noise that the Chargers were fucked anyway after blowing 3rd and 17, or that they couldn't stop the Broncos from moving the chains. Those are all irrelevant to the decision they had at 2:02.
I'm not even sure why you are bringing this up. This was only discussed in the context of the failure of the Chargers in general to force a punt in the last 4 minutes, and that was their best opportunity.
Most teams won't pass because of the increased risk factor, but calling the TO at 2:02 allows the Broncos the chance to think about it. A few teams trust their QB enough that they'll entertain the thought (i.e. the teams that have Peyton, Tom Brady, or Aaron Rodgers). Didn't someone mention yesterday that the Broncos threw on 1st down at 2:02 in the actual game?
The announcer doing the play by play described it in a surprised delivery, since it was unexpected. Whats funny is the only reason some people in the thread are saying take the timeout after the 2 min warning was because of Mannings pass. A 3 yard pass. If thats the only safe play Manning could do SD would give him that all day. It was the 6 and 5 yard runs after the pass that sealed the game.