TTP, I would agree that there may be some breakeven point where a roller may/may not provide a positive ROI. Every pond is different, but here are a few data points to consider.

Tracked equipment, ie dozers, are obviously made to "float" on soft soil and not sink, so the track bearing pressure (psi) is very low, like around 6 to 9 psi. Ground bearing pressure for rubber tired equipment can be in the 25-35 psi range and usually roughly equals the internal tire pressure. The pad foot roller I used exerted around 70 psi. I'm hesitant to quote these types of numbers on a public forum and I'm sure anyone can come up with values that differ from these, but the point is that a tracked piece of equipment exerts much less bearing pressure than rubber tired equipment, and much much less than most roller compactors.

My pond cost me in the $60K range and the roller cost $4K for a month rental. The $4K isnt the net addition I paid because if the roller wouldn't have been compacting the lifts, I would have paid for the scraper pan or other piece of equipment to compact. Large tractors with scrapers are expensive ($200/hr range) and I believe I even saved money using a compactor vs. a tractor and scraper pan, which is what my contractor originally wanted to use.

In summary, although there may be scenarios where a roller doesnt provide a positive ROI, I would never use a piece a tracked equipment to compact soil for a pond. A loaded dump truck is another consideration and if its a smaller pond, there are walk behind rollers and other types of inexpensive compactors as well.