Q:

The expression “It is one thing to ... , but another to ...”

I’ve just used this expression in the sentences below, and I wonder if the use of it can be somewhat misleading. More specifically, I’m talking about the “to” preceding “fully appreciate”.
I’ve used it to mean “in order to”, but the usual pattern of this expression seems to lead the listener to another interpretation.

“It is one thing to passively learn about ... but to fully appreciate how and when ... is quite another”.

Here, the “to” is used to form a subject noun phrase instead.
What’s your take on this?

“It is one thing to passively learn about all those various commands in JavaScript by poring over online materials. But to fully appreciate how and when to use each one, I need to try them out in my own code and have them corrected by someone in the know.”

A:

’Tis one thing to be tempted, Escalus,Another thing to fall. (Measure for Measure 2.1.17–18)

The coordinate pairing of infinitives in this construction is so well established that a reader is likely to reach the end of your first sentence waiting for the other shoe to drop. Your then beginning the second with a to infinitive of purpose is thus a kind of garden path. It is grammatically perfectly correct, but not as foolproof for your reader as you can and should make it. 

