I am not a big fan of polemonium........I have always regarded it as a rather 'blah' plant. Nothing very distinctive about it, somewhat insipid flowers......it just never 'spoke' to me. But I quite liked the variegated form! Even without flowering, it has a great delicate, ferny texture and the creamy variegation makes it pop. My experience with it is from a number of years ago but it did stay small/finely textured although not overly long lived as I recall. Likes a cool, partially shady setting and consistent soil moisture. Doubt it would be happy in a hot, sunny location.

btw, Brise d'Anjou (note the spelling) translates roughly to "breeze of Anjou", from the area in France where the orginating nursery was located.

Have planted and maintained Brise d'Anjou and also variegated (creeping) Jacob's ladder 'Stairway to Heaven' and its sport 'Touch of Class'. I think that the creeping Jacob's ladder cultivars may tend to live longer than Brise d'Anjou. Though also mounding, these cultivars are also a bit larger and the variegation includes white rather than yellow. Mine are planted towards the back of mixed perennial beds and receive summer sun protection from the taller blooming perennials of summer.

writing about plants I haven't tried feels like gossiping. Nevertheless, I tried Stairway to Heaven and when it disappeared then I read more about them. If I recall the variegated ones were not long-lived. Many disappeared after a season or two.

OTOH my "plain blue" ones have reseeded responsibly and are a lovely blue. Personally I rather have live plain green plant than a variegated dead one.

I haven't planted species Polemonium caeruleum (plain blue) for numbers of years, rather using variegated Polemonium cultivars in the garden here. My previous experience with the former species, however, was that it really can be hardy and long-lived, even when neglected. I do think that the variegated forms (of P. caeruleum and P. reptans) are not so tough, though they certainly live, in the growing conditions here, for numbers of years.

It's been said before but it makes sense that variegated cultivars of perennials may be weaker than the non-variegated species/wild type (less photosynthesizing tissue). And sometimes variegation may actually be preferable and not just for looks. For a potentially aggressive spreader, like Brunnera macrophylla, the variegated cultivars may prover better behaved. At the same time, I can't remember the loss of any of the variegated Brunnera cultivars here; and that also goes for the very variegated form, 'Dawson's White'.

I tried ‘Brise d’ Anjou’ several times when it was the new, hot plant, in the nineties I think. They lived up to their name: like a breeze they were here today, gone tomorrow.