I went out 92 days in a row, all alone. I actually didn't know that it is seen as a particularly hardcore way to go about it. Now I don't like going out with people because I feel stuck with them! lol
Walking in, say hi to the people smoking out front and see what they are up to. Any guy alone at the bar will be happy to meet you too, and you get to be seen interacting socially. On lookers don't know you just met. When chatting with a person away from their group, ask who they are with and if you can crash their party. Tell them your out solo. If you are cool with it, they will be too. People don't like to go out alone because they are self-conscious about it. If you don't care, you wanted to go out and meet people and you don't need anyone's permission or help, how is that being a sap? Sounds pretty boss to me. And anyone one who finds out that you came alone and met 30 people is not likely to think you are a sap, that's for sure! lol
This is totally alpha, but I usually try to gather a flock of younger guys and lead them around.
If you are cool, you aren't alone for long. Just have fun, and if you have the most fun in the place you being alone yet social is about as good as you can look. And if you have worn away your approach anxiety for the day then if you are not talking to people it's simply because you don't want to... and they know it. View going alone as being independent rather than being lonely. Because really, with hardly any cold approach practice you'll have an easier time meeting people than anyone else there.
Another tip. Dance. One guy who will break the seal on the dance floor will make all the girls happy because they can dance now and you look great and confident if you can cut loose and self-amuse in such a visible fashion.
There are great advantages to flying solo, being a lone wolf. Confidence building not being the least of them.