Calculating Piece Value: Clock

In the common scheme (1, 3, 3, 5, 9), problematic though it is, the clock is worth at least a pawn. This value is magnified in blitz. An advantage in time in a three minute blitz game is worth at least an exchange. When one player is under a minute, and the other is not, the time advantage is worth a minor piece. If one player is under twenty seconds and the other has ample time, the clock is worth a rook unless checkmate is imminent.

Excellent concept and point.  I played a tournament with a control of 40/120 SD/30 d5 this weekend, and my round 5 game saw a time disparity of 1 hour 28 minutes to my opponent's 15 minutes.  I felt like I was up a lot more than the board suggested.

The qualification to your thought might need to be the complexity of the position.  In a tamer position, I might not have felt completely winning.

Well done. Just like for piece values, you are speaking of averages of course. I can say that the value of time is relative based on skill level. Just speaking personally, in my 20's through 40's (when my blitz and tourney skills were 2200+, and higher at peak 2400 USCF rating) my ability to convert material .advantage with low time made that time less of a factor than both earlier in later in my quick and blitz career. Knowledge and experience are a big help. So are quick reflexes and sharp attention, especially when it comes to blitz situations. Delay and increment are a major factor as well; it makes conversion of much material a foregone conclusion for more skilled players in the absence of  serious complications in most cases. How to factor this in I don't know exactly.

Grischuk is the only exception I can think of to this wonderful formulation.

I know several time pressure junkies who can play pretty well in reasonably complex positions on the increment (usually five seconds). Nonetheless, I've seen them drop pieces to two move tactics in such scrambles.

Certainly, as Milliern notes, the complexity of the position is a vital factor in the calculation of the clock's value. As noted by cschess, the age of the player probably contributes in no small measure too.

When there's a disparity in time, using the clock OTB is something I don't see most players doing.

Lets say the two player's times are 40 minutes and 20 minutes. What you can do (sometimes) is delay the critical moments. Wait until the time is 10 minutes vs 30 (or even later) to play that critical pawn break, or attacking idea. Wait to trade the queen, rook, or minor piece and go into that technical endgame. Keep material on a little longer, and then finally go to the next phase when the clocks favor you more. That's something I don't see a lot.

I recall an Aronian - Grischuk game, I think it was this year, where Aronian played a bad rook sac on purpose, because it greatly complicated the position and Grischuk was super low on time. It turned a drawish position into a win for Aronian.

I've done that!

In classical (long) time controls, one thing you need to be wary of is trying to "keep the pressure" on an opponent who is low on time. If your opponent is down to a few minutes left on the clock while you still have the better part of an hour left, there is a strong temptation to move quickly in order to prevent your opponent from using your time to think and calculate.

This is a mistake! If both players are moving quickly, then what use are you making of your extra hour?

In the 2nd or 3rd tournament I ever played, I had an opponent down to literally 1 second (playing on increment).

So I moved fast!

And I lost, lol.

Being on the other end, once I was down to about 5 minutes vs my opponent's 30 minutes. He took a loooong time on each move, and it was very taxing to sit there, trying to calculate everything I could, not knowing when he'd move next, always being afraid to get too deep into any line. After a few moves I was so tired I blundered

I was looking for some reference material about "the time is being a material in chess" I came across to this search. 

Very good post indeed.