I know that you did not ask me bitebits, but I am having trouble resisting to suggest that any new money should be considered in three categories and then apportioned accordingly.  So there is lump sum investing, DCA and buying on dips.  Of course, the apportionment can be made in accordance with personal preferences, yet the initial default position should be 1/3 in each category.  Of course, personal circumstances should allow for both not ONLY how much to apportion in each category, but then how to manage such apportionment within the categories in terms of how much, price intervals and time intervals. 

So my suggestion is to start with the defaults and then tailorize. 

If a person is a no coiner, then it would seem to be smarter (not saying that no coiners are capable of being smart) to be more aggressive in terms of making sure to get a starting stake in BTC.. whichever categories of achieving the initial allocations, and of course, if someone has been a coiner for a long time, including reaching fairly aggressive accumulation levels of something like 10% or more, then they they would have more psychological and financial liberty to spread out their amounts more and not to be worried if they end up NOT buying more BTC with whatever cash that they have had stumbled across.

Seems to me that AlcoHoDL's cousin is approaching this whole matter as if he is already a coiner with a decent allocation into bitcoin, but whatever, peeps can do whatever they are going to do.. including failing and refusing to appreciate that when they do not make sure that they get a stake into bitcoin, that they already tend to have a lot of other investments (including their income) that is likely already allocated into various kinds of fiat denominations.