Im my opinion and I am sure most NHL cappers will tell you the same is that it is never a smart bet to lay +1.5 puck lines on underdogs turning their plus money odds into juice. It is not profitable over the long run due to empty netters being so prominent and are total sucker bets. -1.5 on the favorites however arent bad. Good luck!
Unless you're using a definition of "smart bet" with which I'm unfamiliar, what you're saying here is not true.
You're entitled to your opinion here, but I don't think you understand what profitable means.
Also, I don't know how you can seriously claim to speak for most nhl cappers.
As stated by another capper (who is much smarter than me), "if you're using a book such as Pinnacle, which deals dime run lines, then you'll typically see a reduction in vig when moving away from a money line between relatively evenly matched teams and an increase in vig when moving away from a money line with one team a relatively large favorite."
Therefore, while both a dog and a fav run line can have a positive EV (and in fact more positive than the ML) depending on how evenly matched the teams are, taking a +1.5 will invariably yield higher expected growth due to the fact that you're laying chalk.
This is not my opinion, this is just math.