First of all what are principles? Webster's defines them as
1) a fundemental truth, law, etc. upon which others are based
2a) a rule of conduct 2b)adherence to such rules; INTEGRITY
3) a basic part
4a) the scientific law explaining a natural action 4b) the method of a things operation

All of these definitions revolve around the concept of a foundation upon which all aspects of our life or our actions are based upon. If we do things against our priciples we move away from the foundation, or we are building new foundations. However, foundations are supposed to be solid. Hence, Jesus' parable of building a house on the sand versus building a house on the rock.

We could go on all day with biblical foundation analogies.

Refering back to building a new foundation, that may not necessarily be a bad thing. But refering to James' writing

James 1:2-12 Count it all joy, my brothers, when you meet trials of various kinds, for you know that the testing of your faith produces steadfastness. And let steadfastness have its full effect, that you may be perfect and complete, lacking in nothing. If any of you lacks wisdom, let him ask God, who gives generously to all without reproach, and it will be given him. But let him ask in faith, with no doubting, for the one who doubts is like a wave of the sea that is driven and tossed by the wind. For that person must not suppose that he will receive anything from the Lord; he is a double-minded man, unstable in all his ways.

Testing of our faith could possibly be synomynous with the testing of our principles. Again priciples are fundemental laws, truth. If they have to be changed or moved away from for a time or permanently, then they aren't fundemental or truth.

Bottom line is probably this. When dealing with practical issues, we are refering to sensibly and realistically understanding and dealing with everyday matters (thank you Mr. Webster). What will dictate my priciples? My experiences, or revelation of God's word in my life? Hopefully in the light of the revelation the experiences here on earth will come into focus and become understandable. By the way, I stated that it is God's revelation, not the local church's revelation. Although one would hope that they might match.

I can hardly add to the above comment. Indeed, it was a very similar approach. I contend that the very definition and purpose of a "principle" (in the sense you intend it, where "value" could also be applied) is to draw the line where decisions based upon practicality cease. Unless, of course, practicality is one's governing principle - a rather ruthless way to live, I judge. When a principle or value is suspended for practical reasons, it ceases to be a governing item. In that case, one must ask whether or not he is compromising a principle or if he has discovered a higher principle that must overrule the previously held one thereby dislodging the previous principle from its former place of prominence.

I defer to Kierkegaard.  Have you read 'Fear and Trembling'?

And if 'practical reasons' entail a compromise of faith, then my answer would be 'no'.