Yes. If part of one panel is shaded then the parallel string with no shade would be forced to lower its voltage to match the shaded string causing a drop in output, the output of the entire array is reduced. The ideal arrangement is for each string to be independent which is how the new SMA inverters are designed.
For example; If the array I posted was 2 strings of 8 panels in parallel then the output voltage of the bottom string would drop by ~20v reducing the output of the array another ~60w or so even though there is no shade on the bottom row.
An array in which each string is on an independent tracker is just as shade tolerant as an array with optimizers or micros.