Seriously Lep, it isn't going to make a difference. Considering that you use Solder on a junction after it has a secure mechanical connection, you're not going to be doing any harm. It's not like the wire stops and you drip some solder in there to fill in the space where the conductors aren't reaching to. Besides, used correctly, the amount of added resistance would be negligible. And don't you DARE say that it's going to add distortion. If you did, I'd find some way to slap you in the face through the internet. Yes, I will.