OK we need to make a distinction between venture capitalist holding type companies (private equity firms) whose primary reason for being in business is buying companies with reasonable debt to equity ratios and then streamlining them such that they may be combined with other related owned or acquired companies, and then sold off for a profit, or greatly expanded in some cases, and the companies who use predatory methods to perform their leveraged buyouts. LBO is not really a type of company, it is more closely related to a business practice or model.
Bain & Co has been part of some colossal buyouts that did not work - but in many cases it is unclear of the investment firm's intentions. A huge majority of those deals were not entered into in an attempt to destroy the company, but would fail usually due to finding out the debt to equity ratios were way too high, and in many cases hidden from the investors.
The big negative comes about because a company's success (in the form of assets on the balance sheet) can be used against it as collateral by a hostile company that acquires it. This type of predatory practice is frowned on by nearly everyone, yet I am not here to tell you that there aren't a bunch of these firms who are in business to do exactly that. There are a number of companies whose LBO's fall into this category, yet I highly doubt that unless you know the particulars of any given deal, whether this was specifically going on at Bain. Certainly there are lawsuits every day for these type of deals, and in the end, you are right about one thing - the workers get screwed, especially when they are laid off or their pensions get liquidated.
Many of the big firms that buy other companies including Bain & Co, do also have quite a long list of companies that have been acquired and then sold off that end up much better off, e.g. Staples, Totes (after buying Isotoner), and Sealy are notable Bain success stories. A huge majority are not hostile takeovers. Unfortunately they have about a 50% success rate and in many failed cases, those investment companies lose the entire amount invested.
I take issue with the idea of how much of Bain's investments were aimed at "value redistribution". You don't know that. I never implied they were atruistic at all, or even "job creators" - they are looking for a profit, no doubt. Lots of political rhetoric on both sides.
If you would like to see an example of a tech version of this type of company. Check out Vista Equity Partners.
http://www.vistaequitypartners.com/
Also, lots of investment firms like Merrill Lynch, and Goldman Sachs, have private equity arms that do much the same thing.
It is easy to stand back and cherry pick the failures and then blame their failure/bankruptcy on Romney. I'm not so sure there is proof that Romney used predatory practices to invest in companies. Proof is never needed, though, just get the sheeple to keep repeating the drivel. Politics is perception, and as long as there is enough people willing to disparage a candidate for something, you can usually bring them down.