Not sure what forum you read that on, but any limit on daytime sleep is going to hinder, not help.
More sleep = better sleep
Poor sleep = less sleep
A baby/toddler getting more sleep is easier to get to sleep, sleeps more deeply so wake less frequently. So overall sleep quality continually improves.
A baby/toddler who is over tired will find getting to sleep more difficult, will sleep lightly so wake easily and so overall sleep spirals to get worse.
At 10 months old my youngest was having two 2 hour naps then about 11h unbroken at night. She kept that until 20 months.
At 20 months she moved to a single 3h-4h afternoon nap and 11h at night. She's now 2y3m and she sleeps 12-3pm (I wake her for the school run, she'd sleep an extra half hour if left) and closer to 12h at night.
If you've taken the mindset that your baby needs less sleep so have been discouraging rather than encouraging more sleep - that is probably the root cause of the problem.
The only other thing is I'd add is don't let that teatime nap go past 4.30-5pm, or it will end up affecting bedtime. But 2h-3h awake time before bed is ideal. Any longer and baby will be over tired.