How Does The Economy Grow with Immigration Reform?

I just don’t get this dynamic scoring that Cato is so enthusiastic about. I have a particular problem understanding how it will grow the economy. Back in 2006 before the immigration system got really screwed up we hired a guest worker, Pedro, from Mexico. Since I was somewhat familiar with the tradeoff of illegal immigrants to guest workers for small businesses, I went through the calculations again. We hired Pedro to replace two and a half teenage girls on our payroll. From an efficiency standpoint this worked out for our farm since Pedro could easily do the work the girls were doing. Since he wanted his wages to competitive with the prevailing wages of local illegal immigrants, we raised his salary to cover his portion of the taxes. Using today’s numbers the total tax burden with unemployment and workers compensation insurance would amount to $3,213 or additional 23% burden over an illegal immigrant. So if we assume that the 8.6+ million immigrants are not paying payroll taxes now, when we convert them into quasi-guest workers the employees and employers will transfer some of their spending power to the country in the form of payroll taxes. Whether the extra burden is paid by the employer or the employee, consumer spending is going down. The only winner is the government. The logical conclusion is that if we reduce consumer spending and increase taxes, it will grow the economy. Huh!? This dynamic scoring idea is more political than pragmatic. It sure sounds like they borrowed the idea from Obamacare and global warming.