Maybe it is because I still have this crazy notion that doubling often has shortness in the suit doubled, but I think that 3♣ is a substantially better bid than 1NT. If partner has a minimum, likely either is a safe contract. If LHO has long hearts (which is somewhat likely on the auction so far), I would like to make him bid them a level higher and not alert him to the fact he should finesse instead of playing for the drop. If we have 3NT, it is likely because partner has heart help, I think we are likely to get there via either route. However, if we have 5 or 6 clubs, I think it will be much easier to get there if we start with 3♣. Old-fashioned again I guess: bidding my long suit.