Long weekend in the USA. Enjoy!
One nice thing about online conferences is that one can be in multiple places at once - thanks to recorded presentations being made available immediately (instead of weeks or months later when the excitement of the conference has faded). In this case, I caught up on a few presentations I wasn’t able to attend at last week’s TOCICO conference.
Boaz Ronen & Shimeon Pass talked about a familiar topic - “Where Should the Constraint Be and What to Do About It?” It’s familiar because I’ve heard a number people in the TOC community talk about the idea of deciding where the constraint should be, instead of discovering it by looking for piles of inventory or work in process. This is a more strategic view of using the TOC focusing steps and makes a lot of sense. They talked about the current constraint and the true constraint to differentiate. As I was listening, I thought of the idea of bottlenecks as being the current constraint - the thing we want to “bottleneck bust”, whereas the true constraint is the real lever that we’d want to use in the business to drive flow.
With that, they then adjusted the Five Focusing Steps to the Unified Focusing Steps:
Determine the system's goal
Determine measures of performance
Identify the current constraint and the true constraint
Decide how to exploit the current constraint
Subordinate the system to the true constraint
Elevate the current constraint(s) until the true constraint becomes effective
Elevate the true constraint
If the true constraint was "broken," go back to step 3
Graham Scott & Vicky Mabin talked about budgeting and accounting with “Using TOC to Investigate the Real Problem with Budgeting.” Mostly it was Graham Scott speaking about research he did with Vicky Mabin, but it was an entertaining look at all the challenges (undesirable effects) that arise from the traditional way companies do their annual budgeting process - and what happens when the assumptions inevitably change. The presented a number of TOC-familiar thinking process trees.
Rob Newbold has been on a long journey to really understand “How to Make Buffers Your Friends.” And this talk was a nice combination of traditional introduction to Critical Chain Project Management and some new thoughts about how to really take advantage of buffers. The thing that jumped out in his presentation was the nice way he took the familiar Lead Time vs Touch Time discussions for individual activities (actual touch time is often quite low in knowledge work - interrupted by multitasking, meetings, drop in requests, etc) and then combined that with the fact that projects are usually a series of dependencies and you could really see how the way we plan just falls apart. It was also a nice way to highlight where those buffers are really coming from - its from the waiting time, not from the touch time.
He also took this conversation to suggest a different way to display the typical CCPM fever chart - that shows % buffer consumption (vertical) vs % longest chain complete (horizontal). His variant uses the same information but displays time on the horizontal axis and % longest chain complete on the vertical. Since the buffer is a time dimension, it can be overlayed on the horizontal axis. (Copies of the slides would make a lot of sense here.)
Philip Marris described ‘The "2 for 1 Rule" to Reduce Lead Times and Work In Progress’. It is a simplification of the “stop releasing” rule that shows up in conversations in Lean and TOC. The idea of “stop releasing” is to lower the water levels so you can find the real bottlenecks in the system, under the assumption that the shop floor or project environment is flooded with way too much work. People often resist this blanket suggestion, so Philip came up with a simple modification: Only release new work for each two completions - that might be one new project for each two project completions; or it might be work orders on a production shop floor.
As with many scenarios where the work-in-process has flooded a system, finding ways to “stop starting and start finishing” are always beneficial. Work flows through the system faster. And Philip joked that you might even be forced to learn some things about how your shop floor system works (or doesn’t).
Henry Camp often gives interesting talks, describing how he is taking the TOC principles into his business. This time he is “Capitalizing on Constraint Shifts” - the constraint shift being the massive upset in the aircraft parts supply chain as the global pandemic hit. Two things struck me about his talk - the first being his variation on the Four Pillars of TOC: he makes it five. He takes “never say I know” out and adds in “Tolerance of uncertainty” and “Openness to improve.” And this story certainly reflected these pillars - the massive drop in business for spare parts when the airlines scaled way back on flights was a huge upset in the parts supply chain. And on top of that, he had to think about how to survive and recover from a situation which seemed hopeless.
But further thinking - being open to improve - took him down the second element that jumped out which was the massive vicious cycle that airlines are in: they have to preserve cash flow so they cut back on everything, including maintenance. This eventually destroys maintenance capacity, which starts to anger customers who are coming back. So they have to buy parts and restart maintenance. But this puts them in danger of losing more money than they make if customers are slow to come back. Which puts them back into the same boat - cut back on spending. Henry drew this as an “infinity loop” rather than a single-loop vicious cycle.