I wouldn't say that merely using the IDE seems to be enough to cause my computer to want to use its fans. However, when I do a full build or full test suite on a larger code base, with any compiler or build tools, it sometimes results in the fans spinning up.
So my instinct is that it really depends on how often you're compiling code and how long. If you're constantly in compile cycles, it seems conceivable to me you'd lose out on some sustained performance with a MBA as opposed to a MBP.
And yes, I've had 100% single-core utilizations result, over time, in the fans spinning up. But it takes a while (~20 minutes?).