I'm not him but let me answer you on that as i have rented delegation and have recently renewed it.
I paid about 90 SBD worth of SP delegation from blocktrades which will be good for 3 months.
Currently at about almost 1900 so I get a curation reward of about 2-3 SP a week normally so it's bad.
I tried at one point front running heavy bot users as well as those that get curie, utopian and dTube accounts and curation I got there was better at around 10 SP a week. However that week period I was not able to support anyone else because my focus was curation rewards.
If I would self vote I would need to be at least 80% in terms of self voting to get the ROI back taking in account that the value of SBD does not change drastically.
I've also tried voteselling as an exercise for a post and it comes to about roughly the same at 8 SBD -11 SBD (the 11 is there because I was too lazy to turn off my steemauto for those that I autovote) in a week.
So if you would delegate to a bot which can net you 95% returns or vote sell which can bet you 85% return it is possible for you to get back your ROI.
Now if you take my route which is manually curating and helping newbies you are bound to take in a loss. A lot have criticized my way of throwing my SBD away by spreading my votes to new accounts instead of concentrating on retrieving what I paid for my delegation. My answer is I'm doing it to make the community better by encouraging good content. Oh and I have recently started not selfvoting last week I did not self vote once so call me crazy and throwing money but to me there is something if you want to make this Platform be better in the long run.
The choice ultimately is yours.