The Xcal isn't permanently "bonded", it just can only be used on one vehicle at a time. Otherwise, everyone and their brother would just buy one and share it. Its basically like copyright protection on DVD's, although I don't know of anyone that's hacked an Xcal.
Also, you will have a tune custom written for your truck and your mods to get the most out of it. The tuner doesn't raise your compression, it would require physical changes to the motor to do that. They typically modify fuel curves and timing advances, which could possibly require a different octane rating to prevent detonation. The tunes can be written for whatever octane you want to use, so you don't have to increase your fuel cost, although the most power will usually come from a 93 octane tune. On the flip side, you can have an economy oriented tune written to help save fuel.