As an example, Nick's [link|https://www.ifixit.com/Guide/ThinkPad+T420+Keyboard+Replacement/87337|T420] guide has the following prerequisites:
[quote|format=featured][link|https://www.ifixit.com/Guide/ThinkPad+T420+Keyboard+Replacement/87337|Keyboard] -> [link|https://www.ifixit.com/Guide/ThinkPad+T420+Keyboard+FRU+Replacement/179655|Keyboard_FRU];
[link|https://www.ifixit.com/Guide/ThinkPad+T420+Keyboard+Replacement/87337|Keyboard] -> [link|https://www.ifixit.com/Guide/ThinkPad+T420+Battery+Replacement/179647|Battery];[/quote]
[quote|format=featured][link|https://www.ifixit.com/Guide/ThinkPad+T420+Hard+Drive+Replacement/78827|Hard_Drive] -> [link|https://www.ifixit.com/Guide/ThinkPad+T420+Battery+Replacement/179647|Battery];[/quote]
[quote|format=featured][link|https://www.ifixit.com/Guide/ThinkPad+T420+Memory+Replacement/87338|Memory] -> [link|https://www.ifixit.com/Guide/ThinkPad+T420+Battery+Replacement/179647|Battery];
[link|https://www.ifixit.com/Guide/ThinkPad+T420+Memory+Replacement/87338|Memory] -> [link|https://www.ifixit.com/Guide/ThinkPad+T420+Keyboard+Replacement/87337|Keyboard];
[link|https://www.ifixit.com/Guide/ThinkPad+T420+Memory+Replacement/87338|Memory] -> [link|https://www.ifixit.com/Guide/ThinkPad+T420+RAM+slot+-+Bottom+Replacement/179649|RAM_Bottom];
[link|https://www.ifixit.com/Guide/ThinkPad+T420+Memory+Replacement/87338|Memory] -> [link|https://www.ifixit.com/Guide/ThinkPad+T420+RAM+-+Keyboard+Replacement/179652|RAM_Keyboard];[/quote]
Shown graphically, that would be:
[image|97556]
Note that prerequisites are not recursive. The Memory guide depends on doing the Keyboard step first, but it does ''not'' depend upon Keyboard_FRU which is why Nick split it into a separate step.
That means the example graph given in the question is incorrect because each guide must explicitly specify all prerequisites. It ought to look like this:
[image|97557]
As for tools, iFixit's software does not yet give regular users an easy way to split a guide into parts. Admins can duplicate a guide and remove the overlap, but most people will have to manually create a new guide and move the content piece by piece.
