Leads and lags appear as mystery elements in reports. I prefer to add them as separate activities to make the lead or lag, plus dependencies, clear. I am thinking about the mouseover info you get in Web sites.

When leads and lags are not identified as separate activities, there are mystery gaps and overlaps the project manager has to explain to everyone else.

When leads and lags are identified as separate activities, the overall chart/report is too big and too complicated.

On something like a Gantt chart, a lead could be a special activity with a pale colour compared to the parent activity. The lead and lag parts of activities would be lightly highlighted in some way to just indicate it is a lead or lag. You could then see the visual alignment to the predecessor.

A mouseover could then display the lead and lag details. A click could expand the display to show the details. The chart/report would keep most of the complications hidden, keeping the chart/report down to a manageable size. You would drill down only into the details relevant to your activities. Any viewer of the chart/report could investigate the details of their parts without complicating the overall chart/report.