Short answer: Risky and potentially illegal.
I'm also from Maryland and have done a
ton of research on this, some of which involved talking to cops and prosecutors, as well as lots of case law.
Maryland's sole knife carry law,
CR 4-101, makes it illegal to carry a dangerous weapon
concealed. What is a dangerous weapon? It's actually a bit vague but it includes "dirk knife" and "bowie knife." The big problem is these terms are never defined. Per several police officers and one State's Attorney, as well as case law I found where the knife was described, these two terms have the potential (but not the 100% certainty) of being applied to
any fixed blade knife carried conceal. All folding knives, on the other hand, are specifically exempted from this law (because they are "penknives" per case law) and are thus assured of being legal.
Case law I read showed me a few important things to consider. First, when you carry a weapon of any kind concealed, you have to actually be suspected of breaking the law for the police to find it. Breaking the law includes traffic offenses, just so we're clear. I have yet to find a case where the defendant wasn't doing something overtly stupid or intentionally divulged they were carrying a knife. When found, and no other serious crime is suspected, it is common for the officer to issue a citation and let the courts figure out of the knife is actually illegal. In the cases where the knife was truly incidental to something like a traffic offense, the charges were dropped or some kind of agreement was reached in exchange for the charges being dropped (aka nolle prosequi). Cases with more serious crimes made the knife charge small potatoes by comparison.