I am guilty of being practical in this matter. I have access to LN at work. Have I tried this on blades of my own? Of course. There just wasn't enough benefit shown to be worth the money spent for the type of steels I use.
I'm heat treating the low alloy steels I use, optimally, and those blades are not likely to have any retained austenite to convert with LN. So it's money wasted on a process that adds nothing to the tool. It might even risk adding greater stresses.
For anyone really interested in making their own blades and doing their own heat treatment, stick to the simple methods. Really, before the 1940's or so, millions of very serviceable blades of all types have been manufactured without benefit of LN. In the end, it comes down to practicality.