Lightroom :: Execute PS Droplet After Exporting Set Of Images

I have been trying to get Lightroom to execute a PS droplet after exporting a set of images. The droplet runs a set of actions which performs certain sharpening and NR steps. What I've been noticing is that if the number of images is too high, the droplet execution fails. Apparently, if the number of images is past 40-50, multiple droplet commands are passed to PS simultaneously and causes PS to fail. PS cannot execute actions simultaneously on multiple images at the same time. The error returned is "Could not complete the Play command because the action is already playing".
 
Here is what I've discovered by experimenting with droplets on the command line without LR initiating them:
 
There is an inherent limitation in the number of characters that can be pass to a command in the Windows OS. That limitation is right around 2048 characters. For example, if I want to pass 30 images to a droplet for execution, the command would look like:
 
mydroplet.exe c:/path/image1.jpg c:/path/image2.jpg c:/path/image3.jpg...etc
 
If the total number of characters in this command is more that 2048, the droplet crashes because you have exceeded the string limit of characters for Windows. If your source directory path is long enough like, C:UsersMynameDocumentsMy PicturesTalent Show 2008, each image can use up 50 or more characters within that command. You exceed the limit with just 40 images. My suspicion is that if you export more than this limit, LR breaks up the export into a series of droplet executions by executing multiple droplet commands. I confirmed this because as I increased the number of images exported out of LR, or placed them deep in the directory hierarchy, I can see more and more droplet commands being executed in Task Manager simultaneously. As soon as I pass 40 images, 2 droplets start running, and PS fails due to the error I previously mentioned.
 
What I don't know is why LR executes them simultaneously? Why not in series so that they will not "clog" up PS?