No, engines that had 55/80 on one or more cylinders proved to be completely fine many times. Read Mike Busch's (many) articles about big bore TCM engines.
The compression in the test has little to do with the pressures inside a running engines.
I wonder what is so fundamentally different between Lycos and Contis?
Mike Busch has written many articles on this topic:
Quote (http://www.avweb.com/news/maint/182902-1.html?redirected=1)
(...)
"Never allow a cylinder to be pulled on the basis of a single compression test. For one thing, the standard differential compression test is notorious for giving non-repeatable results. A cylinder that tests 55/80 today might easily test 68/80 after two more hours in service. Mechanics should treat compression readings the way doctors treat blood pressure readings: no conclusions should be drawn until at least three successive measurements have been taken to establish a baseline. In the case of aircraft engines, the measurements should be separated by at least a few hours of operation.
Furthermore, there's nothing magic about 60/80. It's quite common for some engines to operate quite happily with compression readings in the 50s. Anytime a questionable compression reading is observed, it's important to determine where the compression is being lost. If air can be heard escaping from the exhaust pipe, then the exhaust valve is leaking...a potentially serious problem, and one likely to deteriorate fairly quickly. On the other hand, if air is heard coming from the breather line or oil filler cap, the leakage is coming past the rings...a much less worrisome situation. In fact, low compression readings due to leakage past the rings can probably be disregarded unless it is accompanied by an alarming increase in oil consumption."
(...)
That I agree with, and it is more or less what I said (e.g. low comp readings are not going to by themselves cause a loss of power because the gases can't escape fast enough, but are a likely pointer to more serious problems and need to be investigated) but that's very different to what was written or implied previously.
Nobody should throw away a cylinder which reads 50/80 but then I am sure nobody would because they cost a thousand quid or so.
But if you are 50/80 and stick a borescope down the plug hole and see nothing suspicious, that's a bit pointless too. The problem must be investigated because 50/80 is not a properly functioning cylinder. There is something wrong. The engine may go for another 1000hrs but would I fly over the Alps with it (or anywhere else for that matter)? No.
It's a bit like oil analysis. Many argue this is a waste of time because who is really going to tear down an engine making 100ppm chromium (about 20x the normal value) but which runs "fine" and the oil filter doesn't have any, ahem, noticeable pieces of the camshaft in it? And you can't borescope the camshaft (on a 540) without at least removing a cylinder.
Or an engine burning 2 quarts per hour (2-3 times normal). Airworthy? Sure. Now assume you don't have the Cirrus parachute.... 
It's down to attitude to risk. Mike Busch writes great stuff but equally most US pilots (and the vast majority of European pilots) fly what I might call "massively non-demanding" risk profiles.
But that's not the opinion of the Conti specialists today. If you don't find anything wrong during the borescope inspection and if the engine has no exc. oil consumption, no metal in the oil and is not running rough - then it is airworthy. And if it's airworthy then it is airworthy for the alps too.
TCM engines NEVER have the compression readings you know from your Lycoming 540.
The oil analysis, in my understanding, is only useful if you do it over a long period and watch the TREND. The trend is more important than the absolute numbers.
The engine may go for another 1000hrs but would I fly over the Alps with it (or anywhere else for that matter)? No.
If that was my opinion i wouldn't fly a piston engine anywhere. Actually I like a 1500 h engine with a higher oil consumption (not excessive oil consumption!) a bit better than a brand new one with 25 h
It's down to attitude to risk. Mike Busch writes great stuff but equally most US pilots (and the vast majority of European pilots) fly what I might call "massively non-demanding" risk profiles.
Mike Bush flies a Cessna 310 
You are all right with the borescope checks. I should have expressed that abnormal comp values lead to further differential diagnosis when I compared trend analysis from gas turbine engines to trend analysis of piston engines for "on condition" operation. Pulling cylinders because of low compression values is not justified.
I wonder what is so fundamentally different between Lycos and Contis?
I don't know the answer to that, but FWIW it's true in my experience that Lycomings have more consistent cylinder leakage under static test than Continentals. My experience is with small Continentals, but aero engine culture would have it being true for all of them.
The Mooney billionaire's resort!
[quite fitting that this is post#88!!]
LOL! Hilarious!
I thought it was a spoof website, put together by a prankster; now I'm pretty sure that it's genuine. It has the delusional quality of a scam but, maybe as a foreign devil, I'm looking at this through a cynic's eyes.
