Speaking of bridge circuits. A press release with this digram just came to my inbox. A bridge with MOSFETs. Note the diamond bridge with the connections not always on the points. How would you redraw this schematic?
It looks like the schematic layout was the first step to the PCB layout. Like the "style" David A. describes with netnames on each component pin and nothing else, the schematic is a necessary evil in order to design the PCB.
For those of use who realize the importance of design reviews (even by yourself), and don't have the luxury of ATE but require air-breathing technicians to troubleshoot circuit boards, the time spent on schematic layout is paid back many fold.
Many many many years ago, while at a training session for schematic capture software, I asked about automatic off-page location references for networks. The instructor asked me why that was necessary, since the connection is defined. I had to explain the warm-body-troubleshooting scenerio.
As far as bypass cap locations, I want it to be easy to verify bypass caps during a design review. If having them at the primary symbol makes that area cluttered, then include a text note at the cap with the Ref Des of the associated IC. A similar issue are invisible (on the schematic) power and ground connections. If you don't want them on the primary gate of the IC, then have a power-connection gate, which is also a convenient location for the bypass cap.
Definitely diamond, but not all CAD systems allow this.
Some CAD systems demand the dot to recognize the connection. For example, in TinyCAD without the dot a T intersection is not considered part of the same net; when highlighting that net the T branch does not highlight.
One nice thing in a CAD system is the ability to place simulation results and actual measured scope plots directly onto the schematic, in color. The art has come a long way since I was first forced to use Daisy instead of my pencil.
@David, the diamond schematic in my comment doens;t use dots to indicate connections. Should it? That's another alway's debateable convention: dots or no dots. I prefer dots because sometimes having lies cross in unavoidable. When that occurs, a dot makes i clear that there's a connection. Some get around then by having only T interestions, avoiding crosses (+).
I remember Heathkit schematics as being particularly well-drawn. I think a lot of the quality of the older drawings was that mechanical drawing was at that time a required engineering skill and something people did with great pride. A sloppy drawing indicated sloppy engineering. In Jules Verne's The Begum's Fortune (1879), the hero infiltrates into the enemy's Metropolis-like factory through outstanding mechanical drawing ability.
One of my pet peeves is the terrible automatically-generated logic diagrams one gets from logic synthesizers. IMO they're practically useless for anything but the simplest designs -- I'd much rather have textual equations.
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