A Question About Learning Big Bet HE

[QTip]

Preparing to learn big bet HE, and I came across this.

I'm reading through Reuben and Ciaffone's book here. On page 51, they make they following statement:

"Every pot-limit player ought to learn no-limit play. First, it is an easy step. (Going from no-limit to pot-limit is much more difficult.)

This makes me wonder if I should be learning PL first. Has anyone experienced this? Any general thoughts on this matter?