A more plausible argument is that Alvaro Uribe is doing this on purpose right before he leaves office, thus leaving Santos in the position of making nice with Hugo Chávez from a position of strength. Santos has already made a point of talking diplomatically, and thus far seems much less antagonistic than Uribe with regard to Venezuela. Uribe will take all the heat, and Santos can calm things down.
Holy Crap! I actually agree with Greg Weeks on a Venezuela issue
The Colombia/Venezuela FARC spat, the fallout, the timing. Here’s an extract of what Weeks sez and it passes the smelltest easily: