...Looks perfect, thanks so much!...
No worries.
...but how would I have known, when the Patch tool seemed the perfect option?...
Its really down to trial and error to begin with, and then down to experience.
To be honest with you I don't think I've ever used the 'Patch' tool, probably for the reasons you are experiencing now....there are better, easier ways.
When you have a certain task to do the choice of tool to use will become more obvious the more you do until such a time that it just becomes instinctive. You tend to remember what tools do not work for a specific task rather than those that do.....we all remember when things go wrong easier than when they go right...human nature.
...How is the Patch tool so different from the Clone tool? Don't they, essentially, do the same thing?...
Yes they do...ish.
The 'Clone Stamp' directly copies existing pixels, the 'Patch' tool tries to 'Heal', (Which is why its in the same group as the 'Healing Brush' tool), copied pixels with those behind it...be that by the newer 'Content Aware' or 'Normal'.
I'm guessing here but probably either one of them was introduced into PS before the other. Adobe tends to have a policy that nothing gets taken out of a version of PS, they only ever add to it, so if say the 'Clone Stamp' tool, which is far better than the 'Patch' tool, was added later, the 'Patch' tool will still remain as an alternative method.....regardless of whether its superseded by another tool.
There may be certain circumstances where the 'Patch' tool is just perfect for the task in hand but if you've ever used either of the 'Healing' tools you'll know that its not very good over high contrast. This means that unless the surrounding area of the marquee is constant, like say all grass or tarmac for instance, then its not going to handle it very well.
If you try the 'Healing Brush' tool
near a clearly defined high contrast 'edge' you'll see all sorts of strange things happen....its the same with the 'Patch' tool.
...Why did the Clone tool work so much better that the Patch tool?...
I guess its down to the amount of control, its really just a fancy pantsy 'Brush' tool.
The 'Clone Stamp' is essentially 'painting' by copying existing pixels from a source vector...in fact if you open the 'Clone Source' panel and turn off 'Clipped' and reduce the opacity to say 50%, you'll see that what the tool does is to copy the entire layer and move it according to your 'source' offset. From here it creates a 'mask', (although not visible in the layers panel), on which you then paint....if you could see the mask you'd see that all you are doing is painting in white on a black mask....with the brush tool....on a copy of the whole layer....that's been moved.
The 'Brush' tool is probably one of the first we learn. The 'Clone Stamp' tool therefore seems familiar to use, it doesn't seem that different, and as it has all the options of the regular 'Brush' tool including size, feathering, opacity, rotation to name a few, and also the ability to store up to 5 different sources, its very controllable.
The 'Patch' tool on the other has very limited options and although 'Content aware' is good its still unpredictable, despite you being able to choose the source area. Its doesn't allow for any feathering nor opacity but does have 'Structure' and 'Color' settings when used with 'content aware'....although by the time you've worked out what those mean and gone through the 70 combinations...you could have done the job by cloning.
I hope that's helpful in some way.
Regards.
MrToM.