But the value you have to avoid is 0.1, this value is too high. This value + the lag put you in disadvantaged situation (this explain why people see an enemy awp shooting them in the air)
Discussing interp is an endless discussion but i think sir, even you do not have a fair idea of what interp is. Lurrpis just might, but he is not willing to type a wall of text to explain it to you. Let me help you in this regard -
lower interp means a quicker refresh rate on your screen (0.01 interp ~ update rate 100).
higher interp means a much slower refresh of your screen (0.1 interp ~ update rate 10).
0.01 interp - you will theoretically spot your enemy before (milliseconds of an advantage) he can spot you (in a scenario where he has 0.1 interp), similar to a low pinger's advantage, but you cannot hit inaccurate shots (ideally at low pings)
0.1 interp - you can hit inaccurate shots (most easily noticeable with the awp) because server accounts for an extra 100ms of data while calculating hits, but you loose the peeker's advantage
so when you say people see an enemy awp shooting them in the air, that is because your enemy is using the wrong interp ie. 0.1, and not you. People who awp online using the wrong interp, are not able to land a single shot on lan or while on the correct interp, because they are accustomed to hitting lag shots. I myself live in the bad connection area you talk of, but still choose to use 0.01 all the time since i do not wish to hit shots that i wont hit otherwise.