Well, that strategy is not simply about slots. Especially not this early in the game. By crafting only single-day routes, you gain a lot more flexibility. E.g. you can see exactly how much profit you produce per day and market share of the day, as Mondays and Fridays usually are different. You can also fly different prices on different days of the week in order to weaken your competitors in a sneaky way, as he will not see the impact that quick, as he usually looks at the route averages. Further, you can combine different connections much easier and get your plane schedules up. You have better leverage against image deterioration when planes go into c-check when you fly the route with 7 different planes e.g. Etc. etc. It is much more work to setup but it is quite nice to have as it makes things much more transparent. There are a number of players, including me, who started to implement this and it has proven quite successful so far.