what's the fundamental difference?

[gregkavarnos]

15. Without that one does not get enlightened through instructions concerning chanels and winds.

It is said: "Without the instructions that are [regarded] as non-profound,
One does not get enlightened [through instructions concerning]
The channels and the winds, which [are regarded] as profound."
This again is the [same] discussion as before: one needs to depend on the path
That includes, [all] the earlier and later, stages of the three wheels.
Therefore if one does not pracice the lower and upper approaches to liberation -
The four truths, the perfections, definitive meaning, freedom of elaborations,
Developing stage and completing stage -
In a gradual way, like rungs on a ladder,
Or if one enters immediately at the path of desire and so forth,
ie [the path] of channels, winds and drops,
Then the fruit of temporary peace and happiness will not arise,
Not to mention the attainment of perfect enlightenment.
...
17. All thoughts should be known [to be] without contradiction.

It is said: "One should understand that all thoughts in the words
Of the Buddha are without contradiction.
The 84,000 teachings were explained as methods to abandon
The 84,000 kleshas of a single persons mind stream.
All the three wheels, the tantras, etc. [should be practiced] together,
Without selecting and differentitating what is needed and what is not needed.
...

Jigten Sumgon Gongchig Commentary by Rigdzin Chokyi Dragpa The Lamp Dispelling the Darkness