Critical Chain - Eliyahu M. Goldratt [82]
It's dark outside, so she can't see me blushing. "I couldn't have done it alone," I explain. "If it weren't for Professor Fisher's new knowledge and Professor Wilson . . ." "So you are a team. Even better."
We reach her Seville STS. One of these days I, too, will have a Cadillac.
"What do you think. Is it possible to create a full, two-year program that will bring real value? Something of the caliber they heard from you tonight?"
"I think so," I answer. I'm not just telling her what she wants to hear. Based on what I hear from Jim, Johnny and particularly from Charlene, I really think so.
"Good," she slides into her car. "I'll update Christopher. I'm counting on you to update the head of the Executive MBA program."
She takes off. I stroll to my car. The sky is full of stars.
Chapter 22
It's Saturday morning and I'm stuck. What am I going to teach them today? Originally I'd planned to raise the topic of several projects done by common resources of which one is a bottleneck, the topic I call "projects'-bottleneck." No doubt it would lead to a lively discussion. Maybe I could have gotten a clue or two out of it. But now it's too dangerous. Jim will be sitting in my class.
He decided to expand his systems course to also cover projects, and he "needs to get an impression of the students' level of knowledge." What could I tell him? Don't come?
I'm going over the outline I prepared for the course during the summer. Except for the first few lessons, there isn't much in common with what I have actually taught. There are many topics I've skipped, but for a very good reason. They are what some would call academic—resource optimization, sequence optimization, investment optimization. I call them irrelevant. So what am I going to do?
Maybe Jim will be sick? Wouldn't help much. Before the end of the year there are still four, two-hour sessions that I have to teach.
I go over the outline again. Nothing.
What am I looking for? A topic that is relevant; that excludes all optimizations, that I know well. That excludes almost everything else, definitely projects'-bottleneck. Don't even think about it. And the topic must be one that we haven't yet covered in depth. What's left?
Maybe I'll go over the buffers again? The conceptual difference between a project-buffer, feeding-buffer and a resourcebuffer. How many of my students understand that resourcebuffers don't change the elapsed time of the project? Not many, if any.
Good subject, but how much time can we spend on it? Half an hour? Relying on my students' ability to flounder and the fact that I don't have any other ideas, I decide that it's good enough.
"Good morning, class."
"Good morning."
"Good morning, guests."
"Good morning," Charlene and Jim answer.
Ten seconds gone. Didn't help much. I'd better start. "Now that almost all of you have actual experience," I start, "experience implementing what we have learned, I would like to go back and examine the concepts."
They like it.
Before I can continue, Ruth raises her hand. "I have a problem with the concepts."
What a statement. It doesn't sound good coming from Ruth. I force myself not to look at Jim.
Trying to sound nonchalant, I ask, "What's the problem?"
"Suppose that on one of the noncritical paths we are so late that we have already exhausted the entire feeding buffer, and we have started to penetrate into the project buffer. On the critical path itself we are okay."
"Might happen," I agree. "You might run into a serious problem in one of the feeding paths. But what is your conceptual problem?"
"In the situation Ruth just described, isn't it true that the critical path has changed?" Fred answers. "That now the critical path starts at the operation where we have the problem?" I think about it. Before I reach any conclusion, Mark tries to clarify. "We defined the critical path as the longest chain of dependent steps, longest