Betting more than 1 horse per race for the same price is a nonsense of course. I can't believe how little punters in general understand percentages [odds] and how they work.

Everyone has a win/loss bet ratio and an average win price [or average loss for 95% of us]. Whether one has 50 bets in 50 races or 50 bets [5 bets per race] in 10 races, we still end up with a win/loss bet ratio and average price.
How does having more bets in one race improve our winning chances or increase our average winnings [or losses] per race ? Of course it doesn't and if anyone thinks it does, they would also believe 2+2=5 or are indulging in 'convenient' logic, which of course leaves out the maths of % [odds]. 8-)

Following some of the 'logic' here, if we win 1 in 4 races [25% average] from having 1 bet per race, do we now win 4 in 4 races [100%] by betting 4 horses per race? Of course not, but following some of the logic here and the unspoken maths. it alludes too, we should.

The only ratio that can be increased by betting more than one horse per race is the number of races you have a winner in, not number of winners.

Dutch betting doesn't improve our number of winners nor our winnings either. We might win more races but odds [percentages] decrease proportionally to the number of horses we Dutch. I'm talking long term averages here, not a collection of past winning examples [graph spikes] that show higher than average winnings.

Please present your maths if you disagree, not [convenient] logic or examples, because this thread's question is about maths not opinion.