After playing bridge for several months, I feel my declarer play and bidding have improved to a beginner-intermediate level. However, I think my skill at making an opening lead is that of a novice at best. I have memorized some basic rules about evaluating my hand and inspecting the bidding for clues (and plan to do plenty of additional reading), but I'm curious if there are any good ways to practice my opening leads. With bidding and declarer play I can get quick feedback on whether my choices were good or bad, but with opening leads I rarely have any idea if my lead was brilliant, average, or terrible even after the hand is over.
How can I tell if I made a good lead or a poor lead?
I could examine what gives the best score after recording the cards of all players, but I still won't be able to tell if discovering that lead would be possible without knowing everyone's cards.
Is there slightly more guesswork in opening leads than in the rest of bridge?
When I find two leads that seem to be equally good, sometimes I just pick one at random. Obviously professionals would be able to evaluate leads far better than I could, but do they sometimes encounter the same situation and do a mental coin-flip?