For non-word problems, I think i should support perseverance. My arithmetic drill is doable and requires perseverance; Probably ditto for the easy word problems (some at P3/P4 levels);
For word problems, tough choice for me. I feel encouraging him to solve tougher word problems sounds like 拔苗助长

I kinda see Mrs Goh’s view. Boy is not trying enough, and relying on other people to do the thinking for him.

Perseverance (willpower) is a questionable practice and can fail. In this case, teacher is very sure about it and wife also believes it.

Some word problems that require equation .. he has no confidence so perseverance is possibly ineffective.

— am not good at yoga, but I make a serious effort trying. I guess relatively few people are like me. Karma

I guess for my son the math practice feels like yoga to some extent??

compare the piano perseverance?

邓丽君 was weak in math as a pupil but showed perseverance.

— key to perseverance — 温和

— fatigue and 厌学?

— confrontation, strain, losing-cool

— compare the P1 spelling experiences — 3 hours to learn 10 words. I tried teaching him the patterns but completely failed as he was not engaged.