Not that hard
The company I work for has deals with AA and Delta, and part of the Delta deal was that they will comp elite status. So having made Plat (not to mention 1M miles) with AA, 'twas no problem to go Gold with Delta. Then I wrote USAir asking them to comp me to Gold because of the AA (I told them a sad story about relocating from Texas to Syracuse). So here i am, thrice-2nd-tier-elite. So far it hasn't done me much good. But if we're bragging...