If, by "+1" you mean a cartridge in the chamber, yes--a crunchenticker without a round in the pipe is about as useful as a rock if you're in a hurry. I normally down-load the mags by two rounds, though, so I should probably have answered no...
I can't think of many situations when I wouldn't want a round chambered, so ya, I was thinking one in the pipe and a max capacity magazine. I should have included size because one extra round seems a lot more important if your magazine only holds six or seven than it does if it holds seventeen.