That is almost like a rule in Fantasy, and those managers that are chasing points always end up doing just that, bringing in the players one week to late or ditching them one week too early and missing on great hauls.
So is this actually a better 'strategy' to play this game though for longer term? Removing the non performing players of the week then bring in some top players from last week to haul up few points before ended up bringing in some other players that performs better? or is it just better to keep your points and keep up the potential players?
It's actually harder than just leaving the non performing players for a long term play, because you have to think of the budgets too, if you end up getting short on budget, you'll not be able get certain players after some game weeks, even if you could afford them when the league started, it's very rare to have an all round non-performing players for several weeks, but some are worth having than the others.
It's always about luck sometimes, but taking a calculated risk too increases your chances against every opponent, I really didn't like Salah as my captain for the just concluded week and trust me If I was down on the table and playing to catchup with other managers in the pool, I would have gone with Haaland to be very honest, but I predicted that majority of the managers I'm in contention with would have Salah as their captain, so I'd rather take a risk of having just 6 points together with 85% of managers in the entire pool and 95-100% of managers in the top 7, and then try to outsmart them in other areas of the field, than getting more points in every other area of the field and end up losing them significantly to the captaincy.
To win in the pool I believe every strategy actually matters from knowing when to be conservative and not chasing points blindly when you've got everything to lose, to knowing what your other opponents are likely to go for then you think of alternatives that could be logically better and when you can't think of one, then it's way better to be on the same terms as them until you feel confident about a player(your pick) over theirs, especially based of form and fixtures, it's easier to draw such conclusion based on logic, I guess, you might not always be right, yes, but in the long run, I believe you will stand a better chance.
For me, the most important part of Fantasy strategy is selecting players that are dangerous for opponents goal in every single match. It doesn't matter how many points they scored in particular game week, what matters is their constant presence. Luck will sooner or later end up on your side. That is why Trent, Robertson, Cancelo & James are most expensive defenders, they are playing for teams that will get clean sheets often and all of them are really attacking minded and can get assists or goals against even the thoroughest opponents.
That is why Salah will always be better option than Firminho. Salah will play every single game, Firminho will not. Even if Firminho plays, he has what about one shot per target per 90 minutes while Salah has 4-5? Yes last match was a strange one but I am sure Salah will outscore Firminho by heaps of points before season ends.
After that it comes to what Harkorede said about micro tactics which depend a lot about your current goals and positioning in mini league. I am not even bothering with that until last third of the season. For now it is all about maximizing your points and not taking unnecessary transfers/risks.
You should always look at trends for at least 4-5 game weeks. That includes past performances as well as future fixtures. One game means nothing, you have to have larger scope in order to make informed decisions. For instance everybody was buying Cancelo after first 2 GW and now everybody is selling him after 2 blanks and he plays NFO next, WTF? I would rather place triple captain on him then sell him at this point. Same as it was with Trent and Robbo last week and we all know how that ended.