It can be so. But in most situations you make changes due to emotions or due to what you see. I was both in situation when changing bet was good idea, and when i lost money due to changing bet. My calculation says that it would be better do nothing.
May be my opinion is so, because i mostly bet in low leagues, where there lot of fixed matches. After experiments my strategy has fixed bet size until i rebalance my budget.
Well, I'm against making changes based on what you see or based on someone else's opinion, because no one is perfect when it comes to predictions. For instance, you finish making a prediction just before the game starts, someone looks at your game and starts giving his opinion on how you've made errors in your predictions and how you should have alternatively make a different pick, and due to these opinions, you lose confidence in your predictions and then decide to change it. I've also been in a situation where I made a Parlay bet that lasted for a week, the game started and was going well until the 4 day, I was completely confident in my predictions until the team I predicted to win started losing by 2 goals, which made me lose confidence and decided to cash out, but unfortunately for win by the end of the game, it all played out according to my prediction and I totally regretted my actions.