I think the confusing part in the article is that does not stress the fact that an analog recording can not have a signal > 0dBFS.
This can only happen when summing two or more floating point values digitally.
Ardour can also record to 32bit float directly and all signal flow in Ardour is 32bit float.
You may have noticed that the default signal-meters in Ardour are up to +6dBFS. Signals inside Ardour cannot clip. This does not include plugins! Some effects may not support signals over 0dBFS, or other intentionally limit them.
Signals > 0dBFS are always clipped when they reach the boundary to the analog world. e.g. on playback to a soundcard.
“FS” = full-scale. 0dBFS means maxium signal the ADC/DAC supports.
Also when exporting to a fixed-point format. For the latter Ardour offers normalization (it’s on by default).
It’s safe (no information is lost), but there’s no benefit to doing that.
In music production one usually sums many tracks. So ideally the signal level of each individual track is low (say peak -15dBFS) and the peak of the summed result is already in the ballpark around -2dBFS.
The main advantage of recording to float is that you can use for lower levels. It provides ample headroom.
Some soundcards include specs at which levels ADC works best. A general rule of thumb: aim for around -20…-15dBFS when tracking.