This is misleading advice, albeit probably well intentioned. Profit (or conversely loss) depends on the risk:reward you are employing regardless of t/f chosen as the trigger for entry/operation...and there are high probability trading opportunities on any t/f. As for the stress being lighter, this is subjective, the aim with a trading edge is to get to a position in it's execution where there is no stress....as Mark Douglas says, '...the distribution between winning and losing trades as a result of the trading edge setting-up is not known to use in advance...' so there is no point stressing over it, the stress comes when a flawed trading edge is employed and/or insufficient is known about the trading edge being employed, (as discussed in my previous post on this thread,) and/or the inconsistent application of the trading egde which may or may not be as a result of the first point causing a loss of confidence in it/one's self.
G/L
How is it misleading? On an average day there is around a handful of fundamental data points that affect markets. Planning your day and monitoring those data points are essential however, you don't need to stare at charts all day, nor do you need to focus on small time frames (1m - 30m) to make money. Keeping things simple and basing trades off key technical area that support data points you can make a very good living without spending the entire day on the computer.
Edited: just adding to my statement. The stress I am referring to is focus and time spend looking for opportunities, not stress related to entering trades.