As you know there is a configuration setting (Transaction OVZ1, field TMVFP-VFPSP) that locks a given plant / material combination during sales order processing. The advantage of this setting it that ATP calculations are as accurate as they can possibly be. The disadvantage is that due to the plant / material lock only one user can process that plant / material at a time. SAP calls this option a "hard block". This is a pain if you many users trying to sell (and deliver) the same material out of the same plant.
I do see another alternative out there: we turn OFF this lock and activate a less stringent ATP control tool (call it a "soft block" - transaction OVZ2, field TMVF-ACENQ ) that, in essence, tracks ATP quantities by material and attempts to calculate the same ATP result. It looks like this is accomplished by sending plant, material, & quantity lock entries to the ATPENQ table. The advantage of this approach: multiple users can process orders for the same material / plant. The disadvantage: largely unknown - SAP says the ATP calculation may be "unreliable" if multiple users are simultaneously generating orders for a given material. And the big unknown for me is how the nightly Rescheduling program will be impacted - OSS seems to be silent on this question (which may mean that there are no issues?).
It's very curious that Stock Transport Orders (STO's) seem to be totally unaffected by all this. There is no material block on STO's that I can see and the less stringent quantity check doesn't seem to change STO behavior.
So my question for you: what are your experiences with this "soft block" OVZ2 approach? Does it work? Do you get good ATP calculations? Any implications for the sdv03v02 rescheduling program (we run it nightly)?
Thanks in advance for your comments!