In year two, the Ben Ish Chai [BIC] on Vayishlach mentions a criticism of Yaakov Avinu for procrastinating in fulfilling his pledge, his Neder....
Without dwelling on those specific topics - Viz. of promptness and of the seriousness of N'darim - I want to offer a sympathetic way of understanding the BIC Here, and of criticisms of the Avot in general.
The BIC uses a Key word here MUSSAR. The criticism is IMHO not intended to impugn Yaakov's reputation at all. Rather it is to teach US, the readers, a lesson in MUSSAR.
I have upon occasion used this technique myself - unfortunately with the nasty unintended consequence of being chided for criticising the Avot and the listener thereby tuning out my message!
Yes, I guess *I* need Mussar, too! :-). But the point is, dear readers - that the readers of BIC here or of other similar criticisms of Avot should be aware that the intended message - AISI anyway - is to use the Avot as a foil or as a strawman to teach an ethical lesson
And so the criticism aspect should be taken with a "grain of salt" and not necessarily as the actual, factual history of what happened. It's the ethical/moral lesson that ought to be the focal point
As in our case, BIC makes a classic Mussar point; namely that if Yaakov was chided for his procrastination - kol shekein US.
And so to teach US a lesson Yaakov "takes it on the chin" so to speak; but it's NOT meant to take Yaakov "down a peg" in our evaluation of him.