This is true. I experimented with a hard start capacitor (they temporarily give the compressor motor an extra "kick" on startup) and a delayed condenser fan start. I have a Honda eu2000 and a 13,500btu Carrier AC. The hard start cap made starting the AC much easier on the Honda, however as the ambient temperature went up, from 75F to 85F the cap failed to re-start the AC after it had been running. I added a delayed start timer to the condenser fan circuit which allowed the AC compressor to start by itself. The fan started 5 seconds later. This worked at up to 90F. At 95F my modifications failed altogether, simply too much head pressure to overcome at those temps. The Honda went into overload and kicked the breaker.