Consideration for the soil's 'flow through' ability makes a lot of sense. I confess to the 'no no' that your email highlighted. I put a layer of small sized scoria and scoria dust at the base of my pots, just a sparse layer of less than an inch, however I did add a couple of inches of aged chicken manure compost directly on top of the scoria. I have made many substantial drill holes to the sides and bottom of my pots so they dry out quite quickly, on hot days they noticeably wilt and I water them every day, sometimes they wilt again and I then water them again, I know it seems not the way to do it if growing indoors but my plants seem to be growing happily so I don't think they'd be suffering from anaerobic conditions thankfully.I recommend putting a thin layer of aged compost down there... not too much or you stop the flow through... but enough to give the roots something to enjoy when they find it down there. Other than that, put that soil all the way down to the bottom and let the flow through do its thing.