Re: Gene escape
//... and horizontal gene transfer is believed to be more prevalent than inherited gene transfer in some bacterial species. ...//
While I generally agree with the .. er... sediment... of your post, I can't leave that statement alone - I'm pretty sure it's wrong.
Outside the most extreme and incredibly rare example, vertical gene transfer (that is, genes passed from parent to daughter cells) massively outweighs horizontal gene transfer (that is, genes transferred from one cell to another).
To put numbers on it, a bacterium may have something like 1000 to 6000 genes. A horizontal transfer event might be 1 to perhaps 500 genes (with a mean I'd guess of less than 50, max), and that won't occur every generation. For example, for a conjugative plasmid, a horizontal transfer for every 10 cell/generations would be a high rate, and for a virus... well, most virus particles in the wild carry infectious death; only a tiny proportion are misassembled donor cell DNA. Some cells can take up free DNA, but if they took up and replaced a large proportion of their genome each generation then ... they wouldn't be like that for long, and would stop.
But that's not to say that horizontal transfer isn't widespread.