Quoting: BCAPP
A good idea if we had cap space and more RHD depth, but we have 3 NHL D men (Rielly, Muzzin, Dermott), plus a European FA who looks ready (Lehtonen), plus two #7 NHL defenseman (Marincin and Rosen), plus a top prospect (Sandin) who can play LD.
RHD we have one NHL defenseman who wasn't an NHL defenseman 18 months ago (Holl) and one good prospect (Liljegren). A few of the guys above (Lehtonen, Dermott, Marincin) can play RS but except for Lehtonen who I don't know his preference, all prefer LD
If we are signing a D it has to be RD or with trades
I didn't say I wanted a LHD, I made the suggestion if OP really wanted to sign one.
For what it's worth, a player like Dillon is almost exactly what we need. Handedness is less important than fit IMO.