Were these large/standard or bantam cochins?
I love cochins and have both bantam - pens in silver laced and mille fleur - and a couple large hens - a white and a silver laced.
My large hens are fair layers, not great - and my white goes broody twice a year.
My bantam silver laced are laying machines - from 9 girls I average 6 eggs a day - yes they are small but they taste just as great as a big egg.
My mille fleur are good layers but do go broody about twice a year also.
I also have a bantam red cochin hen - Ruby and she goes broody every 12/13 weeks and between clutches lays about 6 eggs (so 24 or so a year) - but she makes up for the lack of egg laying by being a mothering machine. She is, in my eyes, worth her weight in gold.