I don't think that the problem if being able to estimate time is only with programmers. Time estimation is a combination of many factors. In the context of programming or software development, it can be anything from the skills of the developer, constant customer/client scope changes, sudden resource loss, critical vendor bugs that are usually more time consuming and cannot be fixed in-house (if using vendor system), sudden change in company's budget policy and project criticality (i have worked on million dollar projects that are delayed because management does not want to take a risk due to other un-related issues) etc. Unfortunately, all these variables are extremely difficult to estimate.

So even if a programmer is good and can estimate almost accruately from his/her side, these other variables can throw off a project in no time.