I just know this is going to get me in trouble but I couldn't resist...
Jack Dahlgren posted a comment about Theory of Constraints which triggered a response, which is posted below.
I'm not a TOC fan for much the same reasons (as Jack). But I have clients who are, so I've looked at most of the materials. On the shop floor and in the planning offices of aerospace, buffers are used to provide explicit margin (reserve) for critical path items. In many contracts these explicit margins must be shown (in green) on the monthly report. We manage this margin in the weekly status meetings, handing it out and deducting the amount from the reserve.
What strikes me about TOC is two things ---- There is a force of personality behind the "theory" in TOC. This is a powerful incentive be "get behind the idea," rally the troops, get the message, all that EST style stuff we lived through in the 70's
-- It is unique enough and slightly non-obvious to require some work to both understand and practice TOC. When one "understands" you have an advantage over the "unwashed," much like my position on IMP/IMS, so I understand this in a perverse way.On the shop floor (my experience was in furniture manufacturing) it works as long as the process flow set up in the same way - build the shop around TOC (which they did). I was tasked with deploying an ERP system against this process flow, which turned out to be difficult 'cause SAP doesn't work like TOC, of KANBAN or anything else except SAP.
The real trouble I have is that the proponents are such zealots for TOC that engaging them in a sensible discussion is difficult through the narrow pipe of email and BLOGs. Much like the early days of XP, the force of personality is carrying the ball. We'll have to see if the proof turns out to be the same as the theory.
I've been wrong before (and will be again) - who in their right mind would pay $2.51 for a cup of coffee with some hot milk in it???
I just know there will be a barrage of responses here. My first hope is to have Frank Patrick explain this to me in sensible terms around a shop floor model (forget software it ain't the same as shop floor assembly) - the Toyota Production System is an example is a sensible description of buffered and margin managed flow that I now understand.
But there are Microsoft add ons for TOC, so someone is making use of the process and certainly the Goldratt Institute - much like PMI - is making good money of training folks in TOC, like PMP certifications. There is momentum and momentum counts for a lot in the world of ideas.
It's Sunday and I'm still on the proposal, but this too will pass...
