Sorry but I just can't buy into the oil causing this, it all started with high compression, direct injected turbo engines that allow the use of 87 octane JUNK fuel. Anyone that has been around performance engines knows these items don't work well together, if they even have a remote chance, it will require the use of PREMIUM fuel only. Sure, lets strip out everything and anything thats good in the oil to fix a phantom problem that is not the oils fault!
Cylinder pressures need to be decreased at low RPM/high load hence changes in the timing map, Have any of you seen a later model, small 4 cylinder timing map recently? We're seeing 45+ degrees of timing advance in these things!
Pull some timing and /or require premium fuel and viola! I bet the LSPI goes away. Or quit turbocharging 11.5:1 engines if you don't want to mandate Premium.