I designed my first several bikes in full scale and learned to use a CNC by drafting at + 500%. As a welder, I got a real shock seeing what welding does to frame geometry. Welded stuff can "tighten up" (get smaller) and won't see it unless you do stuff in full scale.

I highly recommend doing the full scale drawing and learning to use layout tools properly. I don't know how many people that build bike frames understand the layout aspect of the job but I don't think it's 100%. That is one of the things that Cinelli did that I fail to to is build to final geometry not theoretical. Doing layout is difficult. Mastering layout is something to be proud of.

If you do choose to print a full scale drawing it would be good to have a couple of reference dimensions to check the scale of the drawing. I am not questioning the above tolerances, I just like to have a string tied to real life.