DY, a 5# class HSB on a 5wt will give a fight of a lifetime - I had rather land them quickly on heavier tackle than to risk losing them.
We are fortunate to have a 1/4 acre HSB/BG "grow-out pond" for all takle fishing,in addition to main pond.
The "litle pond" is where my 5wt fly rod will come into play with 2-3# fish.