One more thought here about the pressure....

If there is that much pressure(oil) to come out the filler/dipstick..It would have opened that little "SLIT" in the top rubber hose and release it from there first !!..correct??....unless this was a solid hose without the pressure relief in there!!!........Remember the rush of air when doing the oil change!!!!!!!.Caper.............

 

ive never had a rush of air when i take off my dipstick when i do the oil changes. ive also never seen the slit in the oil(of course i havent looked either) to replease pressure. which line did you guys say that slit was in? either way or reason if the mfg. manual says it sshouldnt be done its usually for a good reason imo.

 

The top line comming off the black plactic oil tank................You need to pinch this off to prime the system in the oil change proceedure..........I checked myself there is a cut in the rubber line for pressure relief!!.....Caper............